Efficient ball-mill procedure in the ‘green’ asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water
作者:José G. Hernández、Eusebio Juaristi
DOI:10.1016/j.tet.2011.06.042
日期:2011.9
activity of (S)-proline-based dipeptides 1a–c has been evaluated in the asymmetricaldolreaction between representative ketones with various aromatic aldehydes under solvent-free conditions in a ball mill. In particular, the methyl ester of (S)-proline-(S)-tryptophan, (S,S)-1c, proved to be an efficient organocatalyst, and the aldolreaction proceeded with good chemical yields and excellent diastereo- and