A novel formaldehyde-mediated condensation reaction of N,N-dialkyl aromatic amines and resonance-stabilized carbon nucleophiles is described. A condensation reaction between N,N-dimethylaniline (4) and ethyl acetoacetate (8) in the presence of formaldehyde in acetic acid took place to give 2-(4-dimethylaminobenzyl)-3-oxo butyric acid ethyl ester (9) together with the dimerization product 7 in 73 and
Substitution reaction of 4-hydroxymethylaniline derivatives with resonance-stabilized carbon nucleophiles and an acid-labile nucleophile, including β-ketoester, 1,3-diketone, α-nitroester, and silylenolether, proceeded efficiently upon heating at 80°C in a neutral solvent system. The reaction was successfully applied to the synthesis of 4-aminophenylalanine.