A flexible synthesis of 2,3-disubstituted indoles from aminobenzyl phosphonium salts. A direct synthesis of rutaecarpine.J Org Chem. 2009 Aug 07; 74(15):5337-41.JO
The reaction of substituted (2-aminobenzyl)triphenylphosphonium bromides with aromatic aldehydes or alpha,beta-unsaturated aldehydes constitutes a new synthesis of 2,3-disubstitued indoles in high yields. The adduct from 4-oxo-3,4-dihydroquinazoline-2-carbaldehyde was an advanced intermediate in the synthesis of several rutaecarpines.