Synfacts 2007(5): 0562-0562  
DOI: 10.1055/s-2007-968481
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

NCNT-Catalyzed Knoevenagel Condensation

Contributor(s):Yasuhiro Uozumi, Yoichi M. A. Yamada
S. van Dommele, K. P. de Jong, J. H. Bitter*
Utrecht University, the Netherlands
Nitrogen-Containing Carbon Nanotubes as Solid Base Catalysts
Chem. Commun.  2006,  4859-4861  
Further Information

Publication History

Publication Date:
24 April 2007 (online)


Significance

Nitrogen-containing carbon nanotubes (NCNT) were used as solid base catalysts for Knoevenagel condensation. The NCNT materials were prepared by chemical vapour deposition of C- and N-containing precursors (acetonitrile or pyridine) over a SiO2-supported Co or Ni catalyst (C. N. R. Rao and co-workers Chem. Phys. Lett. 2000, 322, 333-340; C. Tang et al. Carbon 2004, 42, 2625-2633). The Knoevenagel condensation of benzaldehyde and ethylcyanoacetate was performed with NCNT in EtOH under reflux conditions to give ethyl-α-cya­nocinnamate in 50% yield. The recovered ­catalyst was reused without loss of catalytic ­activity.

Comment

NCNT that was prepared from acetonitrile with SiO2-supported Co catalyst at 823 K had the highest catalytic activity. Non-functionalized carbon nanofibers did not show any catalytic acitivity. TEM observation indicated that uniform NCNT were observed with an average tube dia­meter of 25 nm.