[zai85]

hello..
can knoevenagel reaction catalyzed by lewis acid catalyst??

can anybody help me on this question and hope some of us can give me an explanation on this topic.

as far as i know, knoevenagel reaction is only catalyzed by base catalyst but i heard some fact that this reaction can also being catalyzed by lewis acid catalyst..
but, i still got no information and further reference on this..

hope to get some information...
thank you so much!

[sjb]

It may not be quite what you're after, but for instance http://dx.doi.org/10.1021/ol027081j, specifically references 5 and 12 suggest Lewis acid promotion of Knoevenagels.

S

[AWK]

Chem. Commun., 2007, 2284–2286