Synthesis of Adipic Acid, 1,6-Hexanediamine, and 1,6-Hexanediol via Double-<i>n</i>-Selective Hydroformylation of 1,3-Butadiene

Abstract

A method for the synthesis of the industrially relevant monomers adipic acid, 1,6-hexanediol (HDO), and 1,6-hexanediamine (HMD) via isomerizing hydroformylation of 1,3-butadiene is described. The aldehyde intermediates are protected in situ as acetals to avoid hydrogenation to pentanal. Adipic aldehyde diacetal is obtained in good yields, and the first examples for the conversion toward adipic acid, 1,6-hexanediol, and 1,6-hexanediamine are shown.