Synthesis of p-Coumar-, Coniferyl- and Sinap Aldehydes

Abstract

p-Coumar-, coniferyl- and sinap aldehydes were synthesized in good yields by new two synthetic methods. 1) The aldehydes were prepared by a two-carbon homologation of p-hydroxybenzaldehyde, vanillin and syringaldehyde with 2, 4, 4, 6-tetramethyl-5, 6-dihydro-1, 3-oxazine in the presence of n-butyllithium in anhydrous tetrahydrofurane at -77℃. 2) The aldehydes were also prepared by reduction of the corresponding p-hydroxycinnamic acid chlorides with lithium tri-t-butoxyaluminohydride in anhydrous diglyme at -77℃.