Synlett 2019; 30(16): 1895-1898
DOI: 10.1055/s-0037-1611757
letter
© Georg Thieme Verlag Stuttgart · New York

Selective Protection of Secondary Alcohols by Using Formic Acid as a Mild and Efficient Deprotection Reagent for Primary tert-Butyldimethylsilyl Ethers

Krishna Sapkota
,
Faqing Huang*
Department of Chemistry and Biochemistry, University of Southern Mississippi, 118 College drive, Hattiesburg, MS, 39406, USA   Email: Faqing.huang@usm.edu
› Author Affiliations
This work was supported by development fund from the University of Southern Mississippi, Hattiesburg, MS, USA.
Further Information

Publication History

Received: 16 January 2019

Accepted after revision: 27 February 2019

Publication Date:
19 March 2019 (eFirst)

Abstract

A mild, efficient, and environmentally friendly method for the selective protection of secondary hydroxyl groups is described. The method involves the protection of both primary and secondary hydroxyl groups as tert-butyldimethylsilyl (TBDMS) ethers and selective deprotection of the primary TBDMS group with formic acid in acetonitrile/water. The rates of desilylation of primary and secondary TBDMS ethers by different concentrations of formic acid are determined. Formic acid of 5–20% concentration is found to selectively deprotect primary TBDMS ethers while keeping more than 95% of their secondary counterparts intact.

Supporting Information

 
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