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Synthesis 2008(19): 3126-3130
DOI: 10.1055/s-2008-1067272
DOI: 10.1055/s-2008-1067272
PAPER
© Georg Thieme Verlag
Stuttgart ˙ New York1,1,1,3,3,3-Hexafluoroisopropanol: A Recyclable Organocatalyst for N-Boc Protection of Amines
Further Information
Received
16 May 2008
Publication Date:
05 September 2008 (online)
Publication History
Publication Date:
05 September 2008 (online)

Abstract
A simple and efficient protocol for the chemoselective mono-N-Boc protection of various structurally diverse amines with di-tert-butyl dicarbonate using 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as solvent and catalyst is described. The catalyst can be readily separated from the reaction products and recovered for direct reuse. No competitive side reactions such as formation of isocyanate, urea, and N,N-di-Boc were observed. α-Amino alcohols afforded the N-Boc derivatives without oxazolidinone formation.
Key words
amines - Boc anhydride - chemoselectivity - HFIP - organocatalyst - hydrogen bonding
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