Conversion of Alanine and Phenylalanine into Weinreb Amides by Using Different Protecting Groups

Zulfiqar Ali*, Syeda Rubina Gilani, Habib Hussain and Imdad Hussain

Department of Chemistry, University of Engineering and Technology, Lahore, Pakistan

*Corresponding author: Tel: +92 321 4947884; E-mail: zulfi_ali_4@yahoo.com

Abstract

Efficient conversions of amino acids into Weinreb amides were achieved by treatment of amino acids with N, O-dimethylhydroxylamine hydrochloride in basic media. The amino group (-NH2) of amino acids were protected with p-toluene sulphonyl chloride (-OTs) and diphenyl phosphinic chloride (-dpp) to get high yield of the product. The products were purified by flash chromatography and characterized by spectroscopic techniques.

Keywords

Weinreb amides, p-Toluene sulphonyl chloride, Diphenyl phosphinic chloride.

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