In Clayden et al. on p. 696 the following nitroaldol reaction is listed:
Later in the same chapter they explain the Cannizzaro reaction. Why is the yield of this nitroaldol reaction particularly good, while a Cannizzaro reaction is also competing for the benzaldehyde? Is the nitroaldol reaction that much faster?
I looked in some literature and they mostly seem to use nitrogen bases (cyclohexylamine, $\ce{Et3N}$, $\ce{n-BuNH2}$, methylamine, etc.) for these kind of reactions (nitroaldol reaction with aromatic electrophile). The reported yields are also typically lower. See for example the "Literature method" section of the synthesis of 1-phenyl-2-nitropropene on Erowid (which seems to be some kind of precursor to amphetamines, so there is plentiful information about it in comparison to the 1-phenyl-2-nitroethene synthesis listed in Clayden. Can the yields be so different due to the steric hindrance of the additional methyl group?). What is the benefit of these nitrogen bases over $\ce{NaOH}$? Clayden et al. only mentions them with the comment that $\ce{NaOH}$ is not really necessary since nitrogen bases are sufficiently strong for nitroaldol reaction, because the typical pKa value of short chain nitro alkyl compounds is ~10.