Preparation of 3-Methylthiodecanal,a Flavour Compound

Abstract

1-Undecen-4-ol was converted into its benzyl ether in 92% yield by reaction with benzyl chloride in the presence of NaH and was then oxidised with a ruthenium catalysis to give the corresponding aldehyde, which was treated directly with ethylene glycol in the presence of pyridinium p-toluenesulfonate to produce 2-(2′-benzyloxynonyl)-1,3-dioxolane in an overall yield of 87%. This intermediate underwent deprotection of the benzyloxy group and mesylation to give 2-(2′-mesyloxynonyl)-1,3-dioxolane in 90% yield, treatment of which with sodium methyl mercaptide followed by cleavage of the 1,3-dioxolane group afforded 3-methylthiodecanal in 81% yield.