Synfacts 2008(3): 0325-0325  
DOI: 10.1055/s-2008-1042666
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Hartwig-Buchwald Amination on Solid Supports

Contributor(s):Yasuhiro Uozumi, Yoichi M. A. Yamada, Toshihiro Watanabe
V. Zimmermann, S. Bräse*
Universität Karlsruhe, Germany
Hartwig-Buchwald Amination on Solid Supports: A Novel Access to a Diverse Set of 1H-Benzotriazoles
J. Comb. Chem.  2007,  9:  1114-1137  
Further Information

Publication History

Publication Date:
21 February 2008 (online)


Significance

The solid-phase synthesis of N-substituted benzotriazoles via the Hartwig-Buchwald reaction was reported. Thus, the ortho-halo and ortho-aminoarene triazene resins 1, 2, and 4 were prepared from aryl diazonium salts and benzylaminomethyl polystyrene. The Hartwig-Buchwald reactions of 1 with amines, and 4 with haloarenes were carried out with a Pd catalyst to give the corresponding triazene-linked N-substituted 2-anilines 5. 1H-Benzotriazoles 6 were obtained under mild acidic conditions via ortho-aminoarene diazonium salts (36 examples; 1-88% yield, 60-99% purity).

Comment

The Hartwig-Buchwald cross-coupling is a palladium-catalyzed reaction of aryl halides with amines to afford the corresponding anilines, which has become a powerful tool in solid-phase organic synthesis (selected pioneering works: Y. D. Ward, V. Farina Tetrahedron Lett. 1996, 37, 6993; C. A. Willoughby, K. T. Chapman Tetrahedron Lett. 1996, 37, 7181). The palladium catalysts were prepared from Pd2(dba)3 or Pd(OAc)2 as Pd sources and rac-BINAP or 2-(dicyclohexyl­phosphino)biphenyl as ligands. Benzotriazoles are the parent materials for the production of UV absorbers.