Prepn. of polyene aldehyde derivs. esp. all-E retinal

摘要

The prepn. of polyene aldehyde derivs. of formula (I) comprises oxidising the corresponding polyene alcohol (II) in the presence of catalytically oxidising ruthenium cpds. or complexes and in the presence of N,N,N-trisubstd. N-oxides of formula (III). R = COOR1, CHO, CH(OR2)2 or a gp. of formula (a). A = CH2 or CHOH; Q = CH2 or CO; R1 = alkyl, aryl, aralkyl, cycloalkyl, (all opt. substd.); R2 = 1-4C alkyl; or R2+R2 = CH2CH2 or CH2CH2CH2 (both opt. substd. with 1-4C alkyl); R3-R5 = 1-6C alkyl, 1-6C alkoxy or 1-6C alkoxyalkyl; or R3+R4 = 5-6 membered heterocycle.