Subscribe to RSS
DOI: 10.1055/s-0031-1290345
Regio- and Stereoselective Copper-Catalyzed Addition of Aromatic and Aliphatic Thiols to Terminal and Internal Nonactivated Alkynes
Publication History
Publication Date:
10 February 2012 (online)
Abstract
The CuI-catalyzed regio- and stereoselective hydrothiolation of terminal and internal alkynes affords (Z)-β-alkenylsulfides. The following isomerization of the Z-isomers into E-isomers catalyzed by CuI is described.
Key words
hydrothiolation - alkynes - copper catalyst - stereoselective anti-Markovnikov addition - isomerization
Considerable attention is being focused on the regio- and stereoselective synthesis of vinyl sulfides in recent years. Vinyl sulfides are important building blocks in organic synthesis used as precursors for aldehyde and ketone formation, [¹] electronically active poly(vinylene sulfide)s, [²] as reagents in cross-coupling, [³] Heck, [4] and cycloaddition reactions, [5] in the synthesis of polydentate P,S-ligands, [6] as ligands for CH activation [7] and allylic alkylation, [8] as equivalents of enolate anions, [9] and Michael acceptors. [¹0] Many natural products with useful biological and pharmacological properties contain an alkenyl sulfide fragment. [¹¹]

Scheme 1
The addition of thiols to terminal alkynes, catalyzed by transition metals, [¹²] lanthanides and actinides, [¹³] allows to obtain alkenyl sulfides with high regioselectivity, forming either α- (Markovnikov addition) or β-isomers (anti-Markovnikov addition). Formation of the α-isomer involves the insertion of alkyne into M-SR bond followed by the protonolysis of the C-M bond (M = Pd).
![]() | |||||||||||||||||||
Entrya | Alkyne | Solvent, additive (mol%) | Temp (˚C) | Time (h) | Yield (%)b | Z/E ratio of 3 c | |||||||||||||
1 | 1a | none | 20 | 48 | 60 |
3:1
[¹²f]
[¹6f]
[¹9]
3a | |||||||||||||
2 | 1a | none, Et3N (20) | 40 | 4 | 100 |
100:0 3a | |||||||||||||
3 | 1a | none, TMEDA (20) | 40 | 4 | 80 |
100:0 3a | |||||||||||||
4 | 1a | THF | 20 | 48 | 80 |
6.1:1 3a | |||||||||||||
5 | 1a | THF, Et3N (20) | 20 | 48 | 70 |
100:0 3a | |||||||||||||
6 | 1a | DMF | 40 | 6 | 100 |
49:1 3a | |||||||||||||
7 | 1a | i-AmOH, ethylene glycol (10:1) | 40 | 6 | 100 |
1:6.1 3a | |||||||||||||
8 | 1a | i-AmOH, ethylene glycol (10:1) | 80 | 4 | 100 |
1:49 3a | |||||||||||||
9 | 1b | DMF | 80 | 1 | 90 |
20:1
[¹5l]
[²²a]
[b]
3b | |||||||||||||
10 | 1b | i-AmOH, ethylene glycol (10:1) | 80 | 1 | 90 |
1:4 3b | |||||||||||||
11 | 1c | THF or DMF | 40 | 4 | 100 |
0:100
[²0]
3c [²6] | |||||||||||||
12 | 1d | THF | 40 | 4 | 100 |
1:10
[¹²r]
[²¹]
3d [²7] | |||||||||||||
| |||||||||||||||||||
a Reaction conditions: PhSH (1 mmol), alkyne
(1 mmol), solvent (0.25 mL), CuI (3 mol%). b Isolated yield. c Determined by ¹H NMR. |
Stereoselective syn-addition leading to the anti-Markovnikov product, for instance in the reaction catalyzed by RhCl(PPh3)3, begins with the insertion of alkyne into H-M bond with the following reductive elimination (Scheme [¹] ). [¹²g] [i] [l] [m] [q]
It should be pointed out that the β-isomer can be also obtained in simple base-catalyzed addition reactions [¹4] as well as in thermal or photochemical radical processes, [¹5] which, however, are usually not stereoselective.
A recent trend towards replacing precious metal complexes, which, moreover, have to be presynthesized, with cheap and easily available copper complexes or salts, [¹²a] [¹6] prompted us to examine the possibility of the copper-catalyzed hydrothiolation of alkynes. Copper complexes are known to have good affinity towards triple bond and therefore can activate it (as Lewis acids) towards nucleophilic attack.
Using the reaction of thiophenol with phenyl acetylene as a model we tested several copper salts and found that only CuI gave a good result (Table [¹] ) improving the yield and selectivity of the noncatalyzed reaction.
It is interesting that in the case of Cu2O and CuSO4 the yield is also high, but the selectivity is poor. The reactions catalyzed by CuI were studied for thiophenol with several alkynes in different solvents and at different temperatures (Table [²] ).
Though the addition of thiols to alkynes can be performed without copper catalyst, especially in the case of PhSH and phenylacetylene, the addition of CuI significantly changes the stereochemistry of the reaction, showing that the catalytic process predominates.
![]() | |||||||||||||||||||
Entrya | Thiol 2 (R) | Solvent | Temp (˚C) | Time (h) | Yield (%)b | Z/E ratio of 3 c | |||||||||||||
1 [³²] | 2b Bn | DMF | 80 | 2 | 72 |
10:1
[¹²q]
[¹4c]
[²³a]
[b]
3e | |||||||||||||
2 | THF | 50 | 6 | 70 | 12:1 | ||||||||||||||
3 | i-AmOH, ethylene glycol (10:1) | 80 | 2 | 70d | 1:4 | ||||||||||||||
4 | i-AmOH, ethylene glycol (10:1) | 80 | 4 | 88d | 1:10 | ||||||||||||||
5 | 2c Hex | DMF | 80 | 2 | 90 |
15:1
[²³a]
3f [²5] | |||||||||||||
6 | DMF | 80 | 4 | 97 | 4:1 | ||||||||||||||
7 | THF | 50 | 4 | 90 | 16:1 | ||||||||||||||
8 | i-AmOH, ethylene glycol (10:1) | 80 | 2 | 90 | 1.3:1 | ||||||||||||||
9 | i-AmOH, ethylene glycol (10:1) | 80 | 4 | 96 | 1:5 | ||||||||||||||
10e | 2d HS(CH2)3SH | DMF | 80 | 5 | 100 |
100:0
[¹7]
3g [²8] | |||||||||||||
11 | THF | 50 | 5 | 97 | 100:0 | ||||||||||||||
12 | i-AmOH, ethylene glycol (10:1) | 80 | 5 | 85 | 4:1 | ||||||||||||||
13 | none | 80 | 5 | 90 | 1.3:1 | ||||||||||||||
14 | DMF | 80 | 12 | 92 |
![]() | ||||||||||||||
| |||||||||||||||||||
a Reaction conditions: Thiol (1 mmol),
alkyne (1 mmol), CuI (3 mol%), solvent (0.5 mL). b Isolated yield c Z/E isomeric ratio determined by ¹H NMR d Formation of disulfide observed e Reaction conditions: Thiol (1 mmol), alkyne (2 mmol), solvent (0.5 mL), CuI (6 mol%). |
In fact we have found that the reaction of thiophenol with phenylacetylene without solvent in the presence of 3 mol% CuI at room temperature gives the same result as the reaction without catalyst, the same yield and same selectivity (Z/E = 3:1, Table [¹] , entry 1 and Table [²] , entry 1).
However, the yield and Z selectivity increased by addition of 20 mol% Et3N or TMEDA at 40 ˚C possible due to solubility of CuI (Table [²] , entries 2 and 3). The addition of Et3N acts in the same way in THF to form Z-isomer as the only product (Table [²] , entry 5). In DMF at 40 ˚C the reaction proceeds fast and with high stereoselectivity (Table [²] , entry 6). The stereochemistry of reaction can be changed completely by using a protic solvent. Thus the studied reaction in the mixture of i-AmOH-ethylene glycol (10:1) at 40 ˚C gives 100% yield and predominantly the E-isomer (Table [²] , entry 7). Increasing the temperature up to 80 ˚C leads to an increase in the E/Z ratio (49:1, Table [²] , entry 8).
The same regularity was observed for aliphatic alkynes. The reaction of hexyne-1 with PhSH at 80 ˚C in DMF and i-AmOH-ethylene glycol (10:1) gives the same yield of the product 3b, but the selectivity is fully converted from a Z/E ratio of 20:1 into 1:4 (Table [²] , entries 9 and 10). The reactions of N,N-dimethylpropargyl amine and propargyl alcohol with PhSH revealed the strong influence of the functional group capable to coordinate the metal on the selectivity of reaction. For these alkynes the E-isomer is formed as the only isomer (Table [²] , entry 11 for CH2NMe2) and predominantly (Table [²] , entry 12 for CH2OH) even in THF.
Several aliphatic thiols were studied in the reaction with phenylacetylene. For all thiols the yield of the products are high but the reaction needs high temperature for the reaction with PhSH (Table [³] ). CuI-catalyzed reactions of aliphatic thiols and phenylacetylene in THF and DMF proceed with high yields and Z-stereoselectivity (Table [³] , entries 1, 2, 5-7). In 1,3-propanedithiol only one SH group takes part in the reaction and only Z isomer is formed (Table [³] , entries 10, 11), on further heating (80 ˚C, 7 h) the reaction leads to the intramolecular heterocyclization and the formation of 2-benzyl-1,3-dithiane (3h, Scheme [²] ). [¹7]

Scheme 2
In the protic solvent, as it was with thiophenol, formation of the E-isomer is observed (Table [³] , entries 3, 4, 8, 9). The E/Z ratio increases with time and at higher reaction temperatures. In the reaction of HexSH with phenylacetylene, even in a protic solvent, both isomers are formed in roughly equal amounts, while after keeping the reaction mixture at 80 ˚C for four hours the E/Z ratio reaches 5:1 (Table [³] , entries 8 and 9). For benzylthiol the initial E/Z ratio of 4:1 (2 h) changes to 10:1 (4 h, Table [³] , entries 3 and 4), the E-isomer appears also for 1,3-propaneditiol (Table [³] , entry 12).
As follows from the data in Table [³] , the yield of alkyl-β-styrylsulfides was near to quantitative in all solvents, the stereoselectivity depends on the solvent. The reaction without solvent is not stereoselective for all thiols (Table [³] , entry 13).
Special trial experiments showed that aliphatic thiols do not react with aliphatic alkynes without copper catalyst under similar conditions. The lower reactivity of alkylthiols becomes especially pronounced in the reaction with N,N-dimethylpropargyl amine and propargyl alcohol in THF.
The product yield for N,N-dimethylpropargylamine reaches 40% at 80 ˚C in 12 hours, while for the propargyl alcohol it is even lower (Scheme [³] ).

Scheme 3 Reaction and conditions: (a) 12 h, 80 ˚C, 40%, E = 100%;(b) 4 h, 50 ˚C, <10%, E/Z = 3:1.
It is known that hydrothiolation of internal alkynes is much more difficult to carry out than terminal alkynes. However, the CuI-catalyzed hydrothiolation of methylphenylacetylene and diphenylacetylene with PhSH proceed very smoothly without solvent at 80 ˚C and high regio- and stereoselectivety to give only one isomer in the case of R = Ph (apparently Z), [¹5b] and mainly the Z-isomer in the case of R = Me (Scheme [4] ). [¹²i] [¹5b] [l] [¹6b] [¹8]

Scheme 4
Entrya | Ethenyl sulfide 3 | Starting Z/E ratio | Temp (˚C) | Time (h) | Z/E ratio (A)b | Z/E ratio (B)b | |||||||||||||
1 | 3a | 2.4:1 |
85 85 |
2 4 |
2.0:1 1.8:1 |
1:6 0:100 | |||||||||||||
2 | 3i [³0] | 2.5:1 |
85 85 85 |
2 4 6 |
2.2:1 2.0:1 1.9:1 |
1:1 1:10 1:30 | |||||||||||||
3 | 3f | 1.9:1 |
85 100 |
4 6 |
1.8:1 1.7:1 |
1:1.3 1:4.2c | |||||||||||||
4 | 3f | 1.9:1 |
85 100 |
4 6 |
1.7:1 1.6:1 |
1:2.5 1:10c | |||||||||||||
| |||||||||||||||||||
a Z/E ratio
determined by ¹H NMR analysis. b Conditions A: heating; conditions B: heating with 1 equiv of thiol and 3 mol% CuI. c HexSCH=CHPh is partly decomposed. |
The obtained data shows clearly that the CuI-catalyzed hydrothiolation of alkynes can serve as a useful preparative method for the synthesis of various Z-β-alkenylsulfides.
Earlier it has been shown that (Z)-alkenylsulfides have been obtained in the reaction of arylpropiolic acid with RSH in the presence of CuI and Cs2CO3. The reaction was not stereoselective for PhSH, though for other RSH Z stereoselectivity was observed. [¹²n] In our opinion, under the conditions described in the work [¹²n] decarboxylation of arylpropiolic acid takes place, and the reaction proceeds with the phenylacetylene formed.
The transition-metal-catalyzed hydrothiolation, if it goes against Markovnikov rule, proceeds as syn addition leading to the E-isomer. On the other hand as we have shown in this paper the Z-isomer can be isomerized into the E-isomer under heating or increasing the time of the reaction in the presence of CuI and thiols. Without CuI increasing the reaction time or its temperature almost no effect on the Z/E-isomer ratio has been observed (Table [4] ). However, in the presence of CuI and especially in a protic solvent (Table [4] ) the amount of the E-isomer increases reaching in some cases 100%.
In summary, a regio- and stereoselective method is developed for the synthesis of Z-β-isomers of alkenylaryl(alkyl)sulfides based on the CuI-catalyzed hydrothiolation of alkynes. The following isomerization of the Z-isomers into E-isomers, also catalyzed with CuI, allows to obtain the E-isomers of alkenylsulfides. CuI apparently acts as a Lewis acid and activates the triple bond towards trans-nucleophilic addition.
- 1
Trofimov BA.Shainyna BA. In The Chemistry of Sulfur-Containing Functional GroupsPatai S.Rappoport Z. John Wiley and Sons; Chichester: 1993. p.659 - 2
Liu J.Lam JVY.Jim CKW.Ng JCY.Shi J.Su H.Yeung KF.Hong Y.Faisal M.Yu Y.Wong KS.Tang BZ. Macromolecules 2011, 44: 68 - 3a
Sabarre A.Love J. Org. Lett. 2008, 10: 3941 - 3b
Wenkert E.Shepard ME.Mcphail AT. J. Chem. Soc., Chem. Commun. 1986, 1390 - 3c
Wenkert E.Fernandes JB.Michelotti EL.Swindell CS. Synthesis 1983, 701 - 3d
Fiandanese V.Harchese G.Naso F.Ronsini L. Chem. Commun. 1982, 647 - 3e
Venkert E.Ferreira TW.Michelotti EL. Chem. Commun. 1979, 637 - 3f
Okamura H.Miura M.Takei H. Tetrahedron Lett. 1979, 43 - 4a
Muraoka N.Mineno M.Itami K.Yoshida J. J. Org. Chem. 2005, 70: 6933 - 4b
Itami K.Mineno M.Muraoka N.Yoshida J. J. Am. Chem. Soc. 2004, 126: 11778 - 4c
Mauleon P.Nunez AA.Alonso J.Carretero JC. Chem. Eur. J. 2003, 9: 1511 - 4d
Trost BM.Tanigawa Y. J. Am. Chem. Soc. 1979, 101: 4743 - 5a
Singh PP.Yadav AK.Ita H.Junjappa H. J. Org. Chem. 2009, 74: 5496 - 5b
Serra S.Fugnti C.Moro A.
J. Org. Chem. 2001, 66: 7883 - 5c
McDoald FE.Burova SA.Huffman LG. Synthesis 2000, 970 - 5d
Yamazaki S. Synth. Org. Chem. 2000, 58: 50 - 5e
Adrio J.Carretero JC. J. Am. Chem. Soc. 1999, 121: 7411 - 5f
Bruckner R.Huisgen R. Tetrahedron Lett. 1990, 31: 2561 - 5g
Singleton D.Church KM. J. Org. Chem. 1990, 55: 4780 - 5h
Gupta RB.Franck RW.Onan KD.Soll CE. J. Org. Chem. 1989, 54: 1097 - 6a
Trofimov BA.Gusarova NK.Malysheva SF.Ivanova NI.Sukhov BG.Belogorlova NA.Kuimov VA. Synthesis 2002, 2207 - 6b
Trofimov BA.Gusarova NK.Malysheva SF.Sukhov BG.Belogorlova NA.Kuimov VA.Al’pert ML. Sulfur Lett. 2003, 26: 63 - 7
Chen MS.White MC. J. Am. Chem. Soc. 2004, 126: 1346 - 8
Fernandez F.Gomez M.Jansat S.Muller G.Martin E.Flores-Santos I. Organometallics 2005, 24: 3946 - 9
Trost BM.Lavoic AC. J. Am. Chem. Soc. 1983, 105: 5075 - 10
Miller RD.Hassing R. Tetrahedron Lett. 1985, 26: 2395 - 11a
Hunter R.Kaschula CH.Parker IM.Caira MR.Richards P.Travis S.Taute F.Qwebani T. Bioorg. Med. Chem. Lett. 2008, 18: 5277 - 11b
Strebhardt K.Ullrich A. Nat. Rev. Cancer 2006, 6: 321 - 11c
Gumireddy K.Baker SJ.Cosenza SC.Premila J.Kang AD.Robell KA. Proc. Natl. Acad. Sci. U.S.A. 2005, 102: 1992 - 11d
Muraoka N.Mineno M.Itami K.Yoshida J. J. Org. Chem. 2005, 70: 6933 - 11e
Sharma VM.Adi Seshu KV.Sekhar VC.Madan S.Vishnu B.Babu PA.Krishna CV.Sreenu J.Krishna VR.Venkateswarlu A.Rajagopal S.Ajaykumar R.Kumar TS. Bioorg. Med. Chem. Lett. 2004, 14: 67 - 11f
Sader HS.Johnson DM.Jones RN. Antimicrob. Agents Chemother. 2004, 48: 53 - 11g
Johannesson P.Lindeberg G.Johansson A.Nikiforovich G.Godoll A.Synnergren B.Le Greves M.Nyberg F.Karlen A.Hallberg A. J. Med. Chem. 2002, 45: 1767 - 12a
Beletskaya IP.Ananikov VP. Chem. Rev. 2011, 111: 1596 - 12b
Ananikov VP.Zalesskiy SS.Beletskaya IP. Curr. Org. Chem. 2011, 8: 2 - 12c
Bichler P.Love J. Top Organomet. Chem. 2010, 31: 39 - 12d
Ide DM.Eastlund MP.Jupe CL.Stockland RA. Curr. Org. Chem. 2008, 1270 - 12e
Beller M.Seayad J.Tillack A.Jiao H. Angew. Chem. Int. Ed. 2004, 43: 3392 - 12f
Kuniyasu H.Kurosawa H. Chem. Eur. J. 2002, 8: 2661 - 12g
Ogawa A. J. Organomet. Chem. 2000, 611: 463 - 12h
Kondo T.Mitsudo T. Chem. Rev. 2000, 3209 - 12i
Ogawa A.Ikeda T.Kimura K.Hirao T. J. Am. Chem. Soc. 1999, 121: 5108 - 12j
Weiss C.Marks TJ. J. Am. Chem. Soc. 2010, 132: 10533 - 12k
Yang J.Sabarre A.Fraser LR.Patrick BO.Love J. J. Org. Chem. 2009, 74: 182 - 12l
Kuniyasu H.Ogawa A.Sato K.-I.Ryu I.Kambe N.Sonoda N. J. Am. Chem. Soc. 1992, 114: 5902 - 12m
Yang Y.Rioux RM. Chem. Commun. 2011, 47: 6557 - 12n
Ranjit S.Duan Z.Zhang P.Liu X. Org. Lett. 2010, 12: 4134 - 12o
Corma A.Gonzalez-Arellano C.Iglesias M.Sanchez F. Appl. Catal., A 2010, 375: 49 - 12p
Field LD.Messerle BA.Vuong KQ.Turner P. Dalton Trans. 2009, 3599 - 12q
Shoai S.Bichler P.Kang B.Buckler H.Love JA. Organometallics 2007, 26: 5778 - 12r
Burling S.Field LD.Messerle B.Vuong KQ.Turner P. Dalton Trans. 2003, 4181 - 12s
Singer H.Wilkinson G. J. Chem. Soc. A 1968, 2516 - 13a
Weiss CJ.Marks TJ. Organometallics 2010, 29: 6308 - 13b
Weiss CJ.Marks TJ. Dalton Trans. 2010, 6576 - 13c
Eisen NS. Top. Organomet. Chem. 2010, 31: 157 - 13d
Weiss CJ.Wobser SD.Marks TJ. J. Am. Chem. Soc. 2009, 131: 2062 - 14a
O’Donnal JS.Singh S.Metcalf TA.Schwan AL. Eur. Org. Chem. 2009, 547 - 14b
Perin G.Mendes SR.Silva MS.Lenardo E.Jacob RG.Santos PC. Synth. Commun. 2006, 36: 2587 - 14c
Kondoh A.Takami K.Yorimitsu H.Oshima K. J. Org. Chem. 2005, 70: 6468 - 14d
Perin G.Jacob R.Azambuja F.Botteselb G.Siqueira G.Freitag R.Lenardo E. Tetrahedron Lett. 2005, 46: 1679 - 14e
Medel R.Monterde MI.Plumet J.Rojas JK. J. Org. Chem. 2005, 70: 735 - 14f
Arjona O.Medel R.Rojas J.Costa A.Vilarrasa J. Tetrahedron Lett. 2003, 44: 6369 - 14g
Trofimov BA. Curr. Org. Chem. 2002, 6: 11212 - 14h
Carson JF.Boggs LE. J. Org. Chem. 1967, 32: 673 - 14i
Truce W.Heine R. J. Am. Chem. Soc. 1957, 79: 5311 - 14j
Truce WE.Simms JA. J. Am. Chem. Soc. 1956, 78: 2756 - 15a
Minozzi M.Monesi A.Nanni D.Spagnolo P.Marchetti N.Massi A. J. Org. Chem. 2011, 76: 450 - 15b
Taniguchi T.Fujii T.Idota A.Ishibashi H. Org. Lett. 2009, 11: 3298 - 15c
Sato A.Yorimitsu H.Oshima K. Synlett 2009, 28 - 15d
Bencivenni G.Lanza T.Leardini R.Nanni D.Spagnolo P.Zanardi G. Org. Lett. 2008, 10: 1127 - 15e
Fernandez M.Alonso R. J. Org. Chem. 2006, 71: 6767 - 15f
Beaufils F.Denes F.Renaud P. Org. Lett. 2004, 6: 2563 - 15g
Fristad GK.Jiang T.Fioroni G. Tetrahedron: Asymmetry 2003, 14: 2853 - 15h
Yorimitsu H.Wakabayashi K.Shinokubo H.Oshima K. Bull. Chem. Soc. Jpn. 2001, 74: 1963 - 15i
Nguyen VH.Nishino H.Kajikawa S.Kurosawa K. Tetrahedron 1998, 54: 11445 - 15j
Benati L.Capella L.Montevecchi PC.Spaglono P. J. Org. Chem. 1995, 60: 7941 - 15k
Yoshida J.Nakatani S.Isoe S. J. Org. Chem. 1993, 58: 4855 - 15l
Benati L.Montevecchi PS.Spagnolo PJ. J. Chem. Soc., Perkin Trans. 1 1991, 2103 - 15m
Griesbaum K. Angew. Chem. 1970, 82: 285 - 16a
Kabir MS.Lorenz M.Van Linn ML.Namjoshi OA.Ara S.Cook J. J. Org. Chem. 2010, 75: 3626 - 16b
Taniguchi N. Tetrahedron 2009, 65: 2782 - 16c
Trostyanskaya IG.Maslova EN.Kazankova MA.Beletskaya IP. Russ. J. Org. Chem. 2008, 44: 32 - 16d
Carril M.SanMartin R.Dominquez E.Tellitu I. Chem. Eur. J. 2007, 13: 5100 - 16e
Beletskaya IP.Cheprakov AV. Coord. Chem. Rev. 2004, 248: 2337 - 16f
Bates CG.Saejueng P.Doherty MQ.Venkataraman D. Org. Lett. 2004, 6: 5005 - 16g
Kwong FY.Buchwald SL. Org. Lett. 2002, 4: 3517 - 17
Demchuk DV.Lutsenko AI.Troyanskii EI.Nikishin GI. Izv. AN SSSR, Ser. Khim. 1990, 2801 - 18
Silveira CC.Perin G.Branga AL.Jacob RG. Tetrahedron 1999, 55: 7421 - 19
Guerrero PG.Dabdoub MJ.Marques FA.Wosch CL.Baroni ACM.Ferreira AG. Synth. Commun. 2008, 38: 4379 - 20
Fitt JJ.Gschwend HW. J. Org. Chem. 1979, 44: 303 - 21
Ritter RH.Cohen T. J. Am. Chem. Soc. 1986, 108: 3718 - 22a
Murahashi S.-I.Yamamura M.Yanagisawa K.Mita N.Kondo K. J. Org. Chem. Soc. 1979, 44: 2408 - 22b
Huang X.Zhong P.Guo W.-R. Org. Prep. Proced. Int. 1999, 31: 201 - 23a
Chu C.-M.Tu Z.Wu P.Wang C.-C.Liu J.-T.Kuo C.-W.Shin Y.-H.Yao C.-F. Tetrahedron 2009, 65: 3878 - 23b
Benati L.Capella L.Montevecchi PC.Spagnolo PJ. J. Org. Chem. 1994, 59: 2818
References and Notes
The products 3a, [¹²r] [¹6f] [¹9] 3c, [²0] 3d, [¹²r] [²¹] 3b, [¹5l] [²²a] [b] 3e, [¹²q] [¹4c] [²³a] [b] 3f, [²³a] 3g,h, [¹8] 3i, [¹²i] [¹5b] [l] [¹6b] [¹7] 3k, [¹5b] [³¹] were identified according to published data. The Z/E isomeric ratio for 3i and 3k was determined by ¹H NMR and ¹³C NMR spectroscopy.
25Typical Experimental Procedure for the CuI-Catalyzed Hydrothiolation of the Alkynes To a mixture of phenylacetylene (1a, 0.102 g, 1 mmol), CuI (0.006 g, 3 mol%) in DMF (0.5 mL) was added HexSH (2c, 0.118 g, 1 mmol) under an argon atmosphere, the mixture was stirred at 80 ˚C for 2 h and then evaporated under vacuum. The resulting oil was diluted with CHCl3 and filtered. The filtrate was concentrated and purified by column chromatography on silica gel (EtOAc-hexane, 5:95) to afford hexyl-(2-styryl)sulfide (3f, [²³a] 0.198 g, 90%; Z/E = 15:1 by NMR) as a colorless oil. ¹H NMR (400 MHz, CDCl3): δ (Z-isomer) = 7.46-7.15 (m, 5 H, Ph), 6,39 (d, ³ J HH = 10.5 Hz, 1 H, PhCH=), 6.20 (d, ³ J HH = 10.5 Hz, 1 H, =CHS), 2.72 (t, ³ J HH = 7.4 Hz, 2 H, CH2S), 1.65 (m, 2 H), 1.38 (m, 2 H), 1.28 (m, 4 H), 0.87 (t, 3 H, CH3); δ (E-isomer) = 7.34-7.16 (m, 5 H, Ph), 6.72 (d, ³ J HH = 16.0 Hz, 1 H, PhCH=), 6.46 (d, ³ J HH = 16.0 Hz, 1 H, =CHS), 2.79 (t, ³ J HH = 7.4 Hz, 2 H, CH2S), 1.69 (m, 2 H), 1.43 (m, 2 H), 1.31 (m, 4 H), 0.90 (t, 3 H, CH3). ¹³C NMR (100.6 MHz, CDCl3): δ (Z-isomer) = 136.94, 128.45, 128.02, 127.57, 126.55, 125.59, 35.80, 31.27, 30.10, 28.15, 22.43, 13.93; δ (E-isomer) = 136.98, 128.48, 128.05, 127.60, 126.35, 125.05, 32.52, 31,25, 29.23, 28.36, 22.41, 13.96.
26( E )- N , N -Dimethyl-3-(phenylthio)-2-propenylamine (3c) [²0] ¹H NMR (400 MHz, CDCl3): δ = 7.22-7.50 (m, Ph), 6.39 (dt, ³ J HH = 16.0 Hz, J HH = 1.4 Hz, 1 H, =CHS), 5.87 (dt, ³ J HH = 16.0 Hz, J HH = 1.4 Hz, 1 H, =CHC), 3.23 (d, J HH = 8.0 Hz, 2 H, CH2N), 2.36 (s, 6 H, CH3N). ¹³C NMR (100.6 MHz, CDCl3): δ = 135.57, 128.93, 128.84, 128.11, 126.55, 126.36, 57.10, 44.91. Anal. Calcd for C11H15NS: C, 68.37; H, 7.81; N, 7.25. Found: C, 68.25; H, 8.00; N, 7.38.
27
3-(Phenylthio)prop-2-en-1-ol
(3d,
E/Z
= 5:1)
[¹²r]
[²¹]
E
-Isomer
¹H
NMR (400 MHz, CDCl3): δ = 7.20-7.49
(m, 5 H, Ph), 6.43 (dt, ³
J
HH = 14.0
Hz, J
HH = 1.4 Hz,
1 H, =CHS), 5.93 (dt, ³
J
HH = 1.4 Hz, 1 H, =CHC),
4.16 (d, ²
J
HH = 7.15
Hz, 2 H, H2CO), 2.15 (br s, 1 H, OH). ¹³C
NMR (100.6 MHz, CDCl3): δ = 132.99,
130.93, 129.96, 128.98, 127.36, 127.05, 63.07.
Z
-Isomer
¹H
NMR (400 MHz, CDCl3): δ = 7.20-7.49
(m, 5 H, Ph), 6.33 (dt, ³
J
HH = 8.0
Hz, J
HH = 1.2 Hz,
1 H, =CHS), 5.90-5.96 (m, 1 H, =CHC),
4.34 (d, ²
J
HH = 7.12
Hz, 2 H, H2CO), 2.13 (br s, 1 H, OH). ¹³C
NMR (100.6 MHz, CDCl3): δ = 136.88, 129.58,
129.04, 128.98, 127.36, 126.91, 59.65. Anal. Calcd. for C9H10OS:
C, 65.06; H, 6.02. Found: C, 65.26; H, 6.19.
( Z )-3-(2-Styrylthio)propanethiol (3g) [¹8]
¹H NMR (400 MHz, CDCI3): δ = 7.19-7.48 (m 5 H, Ph), 6.44 (dd, ³ J HH = 10.8 Hz, 1 H, =CHPh), 6.17 (dd, ³ J HH = 10.8 Hz, 1 H, =CHS), 2.84-2.93 (m, 2 H, =CSCH2), 2.57-2.63 (m, 2 H, H2CSH), 1.82-1.97 (m, 2 H, CCH2C), 1.34 (t, ³ J HH = 7.0 Hz, 1 H, SH). ¹³C NMR (100.6 MHz, CDCI3): δ = 137.20, 129.16, 128.66, 128.25, 126.91 126.74, 41.61, 30.60, 25.64.
292-Benzyl-1,3-dithiane (3h) [¹7]
¹H NMR (400 MHz, CDCI3): δ = 7.25-7.31 (m, 5 H, Ph), 4.25 (t, 1 H, SCH2S), 2.94 (d, 2 H, H2CPh), 2.73 (m, 4 H, SCH2C), 2.05 (m, 1 H), 1.88 (m, 1 H). ¹³C NMR (100.6 MHz, CDCI3): δ = 137.20, 129.16, 128.25, 126.91, 48.82, 41.59, 30.60, 25.60.
30
1-Phenyl-2-(phenylthio)propene
(3i,
[¹²i]
[¹5b]
[l]
[¹6b]
[¹8]
Z
/
E
= 5:1)
¹H
NMR (400 MHz, CDCl3): δ = 7.15-7.55
(21 H, m), 6.69 (1 H, s, Z form), 2.12
(3 H, s, E form, 0.17), 2.01 (3 H, s, Z form, 0.83). ¹³C
NMR (100.6 MHz, CDCl3): δ (Z) = 136.72, 133.50,
131.98, 131.57, 130.79, 128.98, 128.82, 127.96, 127.12, 126.91,
25.55; δ (E) = 137.04,
133.83, 131.96, 131.41, 130.69, 129.03, 128.62, 128.21, 127.33,
126.69, 19.49.
( Z )-1,2-Diphenyl-1-(phenylthio)ethene (3k) [¹5b]
¹H NMR (400 MHz, CDCl3): δ = 7.72 (1 H, d, J = 7.6 Hz), 7.62 (1 H, d, J = 7.8 Hz), 6.92-7.52 (13 H, m), 6.79 (1 H, s). ¹³C NMR (100.6 MHz, CDCl3): δ = 140.83, 137.86, 136.64, 135.64, 134.56, 132.25, 129.74, 129.44, 129.00, 128.58, 128.10, 127.95, 127.36, 125.73.
32Typical Procedure for the Thermal and CuI-Catalyzed Z - to E -Isomerization of Alkenyl Sulfides In each of two Schlenk tubes under argon atmosphere were placed phenyl-(2-styryl)sulfide (Z/E = 2.4:1, 0.106 g, 0.5 mmol). In one of the Schlenk tubes were added thiophenol (2a, 0.055 g, 0.05 mmol), and CuI (0.006 g, 3 mol%). Both tubes were heated at 85 ˚C. The changes of the Z/E ratio was inspected by ¹H NMR spectroscopy. After 4 h without PhSH and CuI the ratio was Z/E = 1.8:1, with CuI and thiol only 100% E-isomer 3a was observed (Table [³] , entry 1).
- 1
Trofimov BA.Shainyna BA. In The Chemistry of Sulfur-Containing Functional GroupsPatai S.Rappoport Z. John Wiley and Sons; Chichester: 1993. p.659 - 2
Liu J.Lam JVY.Jim CKW.Ng JCY.Shi J.Su H.Yeung KF.Hong Y.Faisal M.Yu Y.Wong KS.Tang BZ. Macromolecules 2011, 44: 68 - 3a
Sabarre A.Love J. Org. Lett. 2008, 10: 3941 - 3b
Wenkert E.Shepard ME.Mcphail AT. J. Chem. Soc., Chem. Commun. 1986, 1390 - 3c
Wenkert E.Fernandes JB.Michelotti EL.Swindell CS. Synthesis 1983, 701 - 3d
Fiandanese V.Harchese G.Naso F.Ronsini L. Chem. Commun. 1982, 647 - 3e
Venkert E.Ferreira TW.Michelotti EL. Chem. Commun. 1979, 637 - 3f
Okamura H.Miura M.Takei H. Tetrahedron Lett. 1979, 43 - 4a
Muraoka N.Mineno M.Itami K.Yoshida J. J. Org. Chem. 2005, 70: 6933 - 4b
Itami K.Mineno M.Muraoka N.Yoshida J. J. Am. Chem. Soc. 2004, 126: 11778 - 4c
Mauleon P.Nunez AA.Alonso J.Carretero JC. Chem. Eur. J. 2003, 9: 1511 - 4d
Trost BM.Tanigawa Y. J. Am. Chem. Soc. 1979, 101: 4743 - 5a
Singh PP.Yadav AK.Ita H.Junjappa H. J. Org. Chem. 2009, 74: 5496 - 5b
Serra S.Fugnti C.Moro A.
J. Org. Chem. 2001, 66: 7883 - 5c
McDoald FE.Burova SA.Huffman LG. Synthesis 2000, 970 - 5d
Yamazaki S. Synth. Org. Chem. 2000, 58: 50 - 5e
Adrio J.Carretero JC. J. Am. Chem. Soc. 1999, 121: 7411 - 5f
Bruckner R.Huisgen R. Tetrahedron Lett. 1990, 31: 2561 - 5g
Singleton D.Church KM. J. Org. Chem. 1990, 55: 4780 - 5h
Gupta RB.Franck RW.Onan KD.Soll CE. J. Org. Chem. 1989, 54: 1097 - 6a
Trofimov BA.Gusarova NK.Malysheva SF.Ivanova NI.Sukhov BG.Belogorlova NA.Kuimov VA. Synthesis 2002, 2207 - 6b
Trofimov BA.Gusarova NK.Malysheva SF.Sukhov BG.Belogorlova NA.Kuimov VA.Al’pert ML. Sulfur Lett. 2003, 26: 63 - 7
Chen MS.White MC. J. Am. Chem. Soc. 2004, 126: 1346 - 8
Fernandez F.Gomez M.Jansat S.Muller G.Martin E.Flores-Santos I. Organometallics 2005, 24: 3946 - 9
Trost BM.Lavoic AC. J. Am. Chem. Soc. 1983, 105: 5075 - 10
Miller RD.Hassing R. Tetrahedron Lett. 1985, 26: 2395 - 11a
Hunter R.Kaschula CH.Parker IM.Caira MR.Richards P.Travis S.Taute F.Qwebani T. Bioorg. Med. Chem. Lett. 2008, 18: 5277 - 11b
Strebhardt K.Ullrich A. Nat. Rev. Cancer 2006, 6: 321 - 11c
Gumireddy K.Baker SJ.Cosenza SC.Premila J.Kang AD.Robell KA. Proc. Natl. Acad. Sci. U.S.A. 2005, 102: 1992 - 11d
Muraoka N.Mineno M.Itami K.Yoshida J. J. Org. Chem. 2005, 70: 6933 - 11e
Sharma VM.Adi Seshu KV.Sekhar VC.Madan S.Vishnu B.Babu PA.Krishna CV.Sreenu J.Krishna VR.Venkateswarlu A.Rajagopal S.Ajaykumar R.Kumar TS. Bioorg. Med. Chem. Lett. 2004, 14: 67 - 11f
Sader HS.Johnson DM.Jones RN. Antimicrob. Agents Chemother. 2004, 48: 53 - 11g
Johannesson P.Lindeberg G.Johansson A.Nikiforovich G.Godoll A.Synnergren B.Le Greves M.Nyberg F.Karlen A.Hallberg A. J. Med. Chem. 2002, 45: 1767 - 12a
Beletskaya IP.Ananikov VP. Chem. Rev. 2011, 111: 1596 - 12b
Ananikov VP.Zalesskiy SS.Beletskaya IP. Curr. Org. Chem. 2011, 8: 2 - 12c
Bichler P.Love J. Top Organomet. Chem. 2010, 31: 39 - 12d
Ide DM.Eastlund MP.Jupe CL.Stockland RA. Curr. Org. Chem. 2008, 1270 - 12e
Beller M.Seayad J.Tillack A.Jiao H. Angew. Chem. Int. Ed. 2004, 43: 3392 - 12f
Kuniyasu H.Kurosawa H. Chem. Eur. J. 2002, 8: 2661 - 12g
Ogawa A. J. Organomet. Chem. 2000, 611: 463 - 12h
Kondo T.Mitsudo T. Chem. Rev. 2000, 3209 - 12i
Ogawa A.Ikeda T.Kimura K.Hirao T. J. Am. Chem. Soc. 1999, 121: 5108 - 12j
Weiss C.Marks TJ. J. Am. Chem. Soc. 2010, 132: 10533 - 12k
Yang J.Sabarre A.Fraser LR.Patrick BO.Love J. J. Org. Chem. 2009, 74: 182 - 12l
Kuniyasu H.Ogawa A.Sato K.-I.Ryu I.Kambe N.Sonoda N. J. Am. Chem. Soc. 1992, 114: 5902 - 12m
Yang Y.Rioux RM. Chem. Commun. 2011, 47: 6557 - 12n
Ranjit S.Duan Z.Zhang P.Liu X. Org. Lett. 2010, 12: 4134 - 12o
Corma A.Gonzalez-Arellano C.Iglesias M.Sanchez F. Appl. Catal., A 2010, 375: 49 - 12p
Field LD.Messerle BA.Vuong KQ.Turner P. Dalton Trans. 2009, 3599 - 12q
Shoai S.Bichler P.Kang B.Buckler H.Love JA. Organometallics 2007, 26: 5778 - 12r
Burling S.Field LD.Messerle B.Vuong KQ.Turner P. Dalton Trans. 2003, 4181 - 12s
Singer H.Wilkinson G. J. Chem. Soc. A 1968, 2516 - 13a
Weiss CJ.Marks TJ. Organometallics 2010, 29: 6308 - 13b
Weiss CJ.Marks TJ. Dalton Trans. 2010, 6576 - 13c
Eisen NS. Top. Organomet. Chem. 2010, 31: 157 - 13d
Weiss CJ.Wobser SD.Marks TJ. J. Am. Chem. Soc. 2009, 131: 2062 - 14a
O’Donnal JS.Singh S.Metcalf TA.Schwan AL. Eur. Org. Chem. 2009, 547 - 14b
Perin G.Mendes SR.Silva MS.Lenardo E.Jacob RG.Santos PC. Synth. Commun. 2006, 36: 2587 - 14c
Kondoh A.Takami K.Yorimitsu H.Oshima K. J. Org. Chem. 2005, 70: 6468 - 14d
Perin G.Jacob R.Azambuja F.Botteselb G.Siqueira G.Freitag R.Lenardo E. Tetrahedron Lett. 2005, 46: 1679 - 14e
Medel R.Monterde MI.Plumet J.Rojas JK. J. Org. Chem. 2005, 70: 735 - 14f
Arjona O.Medel R.Rojas J.Costa A.Vilarrasa J. Tetrahedron Lett. 2003, 44: 6369 - 14g
Trofimov BA. Curr. Org. Chem. 2002, 6: 11212 - 14h
Carson JF.Boggs LE. J. Org. Chem. 1967, 32: 673 - 14i
Truce W.Heine R. J. Am. Chem. Soc. 1957, 79: 5311 - 14j
Truce WE.Simms JA. J. Am. Chem. Soc. 1956, 78: 2756 - 15a
Minozzi M.Monesi A.Nanni D.Spagnolo P.Marchetti N.Massi A. J. Org. Chem. 2011, 76: 450 - 15b
Taniguchi T.Fujii T.Idota A.Ishibashi H. Org. Lett. 2009, 11: 3298 - 15c
Sato A.Yorimitsu H.Oshima K. Synlett 2009, 28 - 15d
Bencivenni G.Lanza T.Leardini R.Nanni D.Spagnolo P.Zanardi G. Org. Lett. 2008, 10: 1127 - 15e
Fernandez M.Alonso R. J. Org. Chem. 2006, 71: 6767 - 15f
Beaufils F.Denes F.Renaud P. Org. Lett. 2004, 6: 2563 - 15g
Fristad GK.Jiang T.Fioroni G. Tetrahedron: Asymmetry 2003, 14: 2853 - 15h
Yorimitsu H.Wakabayashi K.Shinokubo H.Oshima K. Bull. Chem. Soc. Jpn. 2001, 74: 1963 - 15i
Nguyen VH.Nishino H.Kajikawa S.Kurosawa K. Tetrahedron 1998, 54: 11445 - 15j
Benati L.Capella L.Montevecchi PC.Spaglono P. J. Org. Chem. 1995, 60: 7941 - 15k
Yoshida J.Nakatani S.Isoe S. J. Org. Chem. 1993, 58: 4855 - 15l
Benati L.Montevecchi PS.Spagnolo PJ. J. Chem. Soc., Perkin Trans. 1 1991, 2103 - 15m
Griesbaum K. Angew. Chem. 1970, 82: 285 - 16a
Kabir MS.Lorenz M.Van Linn ML.Namjoshi OA.Ara S.Cook J. J. Org. Chem. 2010, 75: 3626 - 16b
Taniguchi N. Tetrahedron 2009, 65: 2782 - 16c
Trostyanskaya IG.Maslova EN.Kazankova MA.Beletskaya IP. Russ. J. Org. Chem. 2008, 44: 32 - 16d
Carril M.SanMartin R.Dominquez E.Tellitu I. Chem. Eur. J. 2007, 13: 5100 - 16e
Beletskaya IP.Cheprakov AV. Coord. Chem. Rev. 2004, 248: 2337 - 16f
Bates CG.Saejueng P.Doherty MQ.Venkataraman D. Org. Lett. 2004, 6: 5005 - 16g
Kwong FY.Buchwald SL. Org. Lett. 2002, 4: 3517 - 17
Demchuk DV.Lutsenko AI.Troyanskii EI.Nikishin GI. Izv. AN SSSR, Ser. Khim. 1990, 2801 - 18
Silveira CC.Perin G.Branga AL.Jacob RG. Tetrahedron 1999, 55: 7421 - 19
Guerrero PG.Dabdoub MJ.Marques FA.Wosch CL.Baroni ACM.Ferreira AG. Synth. Commun. 2008, 38: 4379 - 20
Fitt JJ.Gschwend HW. J. Org. Chem. 1979, 44: 303 - 21
Ritter RH.Cohen T. J. Am. Chem. Soc. 1986, 108: 3718 - 22a
Murahashi S.-I.Yamamura M.Yanagisawa K.Mita N.Kondo K. J. Org. Chem. Soc. 1979, 44: 2408 - 22b
Huang X.Zhong P.Guo W.-R. Org. Prep. Proced. Int. 1999, 31: 201 - 23a
Chu C.-M.Tu Z.Wu P.Wang C.-C.Liu J.-T.Kuo C.-W.Shin Y.-H.Yao C.-F. Tetrahedron 2009, 65: 3878 - 23b
Benati L.Capella L.Montevecchi PC.Spagnolo PJ. J. Org. Chem. 1994, 59: 2818
References and Notes
The products 3a, [¹²r] [¹6f] [¹9] 3c, [²0] 3d, [¹²r] [²¹] 3b, [¹5l] [²²a] [b] 3e, [¹²q] [¹4c] [²³a] [b] 3f, [²³a] 3g,h, [¹8] 3i, [¹²i] [¹5b] [l] [¹6b] [¹7] 3k, [¹5b] [³¹] were identified according to published data. The Z/E isomeric ratio for 3i and 3k was determined by ¹H NMR and ¹³C NMR spectroscopy.
25Typical Experimental Procedure for the CuI-Catalyzed Hydrothiolation of the Alkynes To a mixture of phenylacetylene (1a, 0.102 g, 1 mmol), CuI (0.006 g, 3 mol%) in DMF (0.5 mL) was added HexSH (2c, 0.118 g, 1 mmol) under an argon atmosphere, the mixture was stirred at 80 ˚C for 2 h and then evaporated under vacuum. The resulting oil was diluted with CHCl3 and filtered. The filtrate was concentrated and purified by column chromatography on silica gel (EtOAc-hexane, 5:95) to afford hexyl-(2-styryl)sulfide (3f, [²³a] 0.198 g, 90%; Z/E = 15:1 by NMR) as a colorless oil. ¹H NMR (400 MHz, CDCl3): δ (Z-isomer) = 7.46-7.15 (m, 5 H, Ph), 6,39 (d, ³ J HH = 10.5 Hz, 1 H, PhCH=), 6.20 (d, ³ J HH = 10.5 Hz, 1 H, =CHS), 2.72 (t, ³ J HH = 7.4 Hz, 2 H, CH2S), 1.65 (m, 2 H), 1.38 (m, 2 H), 1.28 (m, 4 H), 0.87 (t, 3 H, CH3); δ (E-isomer) = 7.34-7.16 (m, 5 H, Ph), 6.72 (d, ³ J HH = 16.0 Hz, 1 H, PhCH=), 6.46 (d, ³ J HH = 16.0 Hz, 1 H, =CHS), 2.79 (t, ³ J HH = 7.4 Hz, 2 H, CH2S), 1.69 (m, 2 H), 1.43 (m, 2 H), 1.31 (m, 4 H), 0.90 (t, 3 H, CH3). ¹³C NMR (100.6 MHz, CDCl3): δ (Z-isomer) = 136.94, 128.45, 128.02, 127.57, 126.55, 125.59, 35.80, 31.27, 30.10, 28.15, 22.43, 13.93; δ (E-isomer) = 136.98, 128.48, 128.05, 127.60, 126.35, 125.05, 32.52, 31,25, 29.23, 28.36, 22.41, 13.96.
26( E )- N , N -Dimethyl-3-(phenylthio)-2-propenylamine (3c) [²0] ¹H NMR (400 MHz, CDCl3): δ = 7.22-7.50 (m, Ph), 6.39 (dt, ³ J HH = 16.0 Hz, J HH = 1.4 Hz, 1 H, =CHS), 5.87 (dt, ³ J HH = 16.0 Hz, J HH = 1.4 Hz, 1 H, =CHC), 3.23 (d, J HH = 8.0 Hz, 2 H, CH2N), 2.36 (s, 6 H, CH3N). ¹³C NMR (100.6 MHz, CDCl3): δ = 135.57, 128.93, 128.84, 128.11, 126.55, 126.36, 57.10, 44.91. Anal. Calcd for C11H15NS: C, 68.37; H, 7.81; N, 7.25. Found: C, 68.25; H, 8.00; N, 7.38.
27
3-(Phenylthio)prop-2-en-1-ol
(3d,
E/Z
= 5:1)
[¹²r]
[²¹]
E
-Isomer
¹H
NMR (400 MHz, CDCl3): δ = 7.20-7.49
(m, 5 H, Ph), 6.43 (dt, ³
J
HH = 14.0
Hz, J
HH = 1.4 Hz,
1 H, =CHS), 5.93 (dt, ³
J
HH = 1.4 Hz, 1 H, =CHC),
4.16 (d, ²
J
HH = 7.15
Hz, 2 H, H2CO), 2.15 (br s, 1 H, OH). ¹³C
NMR (100.6 MHz, CDCl3): δ = 132.99,
130.93, 129.96, 128.98, 127.36, 127.05, 63.07.
Z
-Isomer
¹H
NMR (400 MHz, CDCl3): δ = 7.20-7.49
(m, 5 H, Ph), 6.33 (dt, ³
J
HH = 8.0
Hz, J
HH = 1.2 Hz,
1 H, =CHS), 5.90-5.96 (m, 1 H, =CHC),
4.34 (d, ²
J
HH = 7.12
Hz, 2 H, H2CO), 2.13 (br s, 1 H, OH). ¹³C
NMR (100.6 MHz, CDCl3): δ = 136.88, 129.58,
129.04, 128.98, 127.36, 126.91, 59.65. Anal. Calcd. for C9H10OS:
C, 65.06; H, 6.02. Found: C, 65.26; H, 6.19.
( Z )-3-(2-Styrylthio)propanethiol (3g) [¹8]
¹H NMR (400 MHz, CDCI3): δ = 7.19-7.48 (m 5 H, Ph), 6.44 (dd, ³ J HH = 10.8 Hz, 1 H, =CHPh), 6.17 (dd, ³ J HH = 10.8 Hz, 1 H, =CHS), 2.84-2.93 (m, 2 H, =CSCH2), 2.57-2.63 (m, 2 H, H2CSH), 1.82-1.97 (m, 2 H, CCH2C), 1.34 (t, ³ J HH = 7.0 Hz, 1 H, SH). ¹³C NMR (100.6 MHz, CDCI3): δ = 137.20, 129.16, 128.66, 128.25, 126.91 126.74, 41.61, 30.60, 25.64.
292-Benzyl-1,3-dithiane (3h) [¹7]
¹H NMR (400 MHz, CDCI3): δ = 7.25-7.31 (m, 5 H, Ph), 4.25 (t, 1 H, SCH2S), 2.94 (d, 2 H, H2CPh), 2.73 (m, 4 H, SCH2C), 2.05 (m, 1 H), 1.88 (m, 1 H). ¹³C NMR (100.6 MHz, CDCI3): δ = 137.20, 129.16, 128.25, 126.91, 48.82, 41.59, 30.60, 25.60.
30
1-Phenyl-2-(phenylthio)propene
(3i,
[¹²i]
[¹5b]
[l]
[¹6b]
[¹8]
Z
/
E
= 5:1)
¹H
NMR (400 MHz, CDCl3): δ = 7.15-7.55
(21 H, m), 6.69 (1 H, s, Z form), 2.12
(3 H, s, E form, 0.17), 2.01 (3 H, s, Z form, 0.83). ¹³C
NMR (100.6 MHz, CDCl3): δ (Z) = 136.72, 133.50,
131.98, 131.57, 130.79, 128.98, 128.82, 127.96, 127.12, 126.91,
25.55; δ (E) = 137.04,
133.83, 131.96, 131.41, 130.69, 129.03, 128.62, 128.21, 127.33,
126.69, 19.49.
( Z )-1,2-Diphenyl-1-(phenylthio)ethene (3k) [¹5b]
¹H NMR (400 MHz, CDCl3): δ = 7.72 (1 H, d, J = 7.6 Hz), 7.62 (1 H, d, J = 7.8 Hz), 6.92-7.52 (13 H, m), 6.79 (1 H, s). ¹³C NMR (100.6 MHz, CDCl3): δ = 140.83, 137.86, 136.64, 135.64, 134.56, 132.25, 129.74, 129.44, 129.00, 128.58, 128.10, 127.95, 127.36, 125.73.
32Typical Procedure for the Thermal and CuI-Catalyzed Z - to E -Isomerization of Alkenyl Sulfides In each of two Schlenk tubes under argon atmosphere were placed phenyl-(2-styryl)sulfide (Z/E = 2.4:1, 0.106 g, 0.5 mmol). In one of the Schlenk tubes were added thiophenol (2a, 0.055 g, 0.05 mmol), and CuI (0.006 g, 3 mol%). Both tubes were heated at 85 ˚C. The changes of the Z/E ratio was inspected by ¹H NMR spectroscopy. After 4 h without PhSH and CuI the ratio was Z/E = 1.8:1, with CuI and thiol only 100% E-isomer 3a was observed (Table [³] , entry 1).

Scheme 1





Scheme 2

Scheme 3 Reaction and conditions: (a) 12 h, 80 ˚C, 40%, E = 100%;(b) 4 h, 50 ˚C, <10%, E/Z = 3:1.

Scheme 4