Reactions of carbonyl compounds with tervalent phosphorus reagents. Part 9. Benzaldehyde with phosphinites in the presence of acetic acid

Abstract

Acylals (8) are produced by the reaction of benzaldehyde with methyl diphenylphosphinite (4a) and carboxylic acids. One diastereoisomer of (8) is formed almost exclusively under mild conditions; the reasons for this are discussed. α-(α-Acetoxybenzyloxy)benzyldiphenylphosphine oxide (8a) is relatively inert to methanol. Analogues of (8), the 3-acyloxy-1,3-diphenylpropylphosphine oxides (9), have been synthesised and used in assignment of structure to the acylals (8).