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Synthesis 2002(14): 2057-2063
DOI: 10.1055/s-2002-34371
DOI: 10.1055/s-2002-34371
PAPER
© Georg Thieme Verlag Stuttgart · New York
β-Tosylethylhydroxylamine: Preparation and Use as a Hydroxylamine Equivalent in Amidyl Radical-Olefin Cyclizations
Further Information
Received
8 February 2002
Publication Date:
26 September 2002 (online)
Publication History
Publication Date:
26 September 2002 (online)
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Abstract
An efficient three-step procedure has been developed for synthesis of β-tosylethylhydroxylamine from commercially available starting material. This compound forms hydroxamic acids which undergo amidyl radical-olefin cyclizations promoted by diethyl chlorophosphite to give functionalized β-tosylethyl-protected lactams, which can be deprotected under mild basic conditions.
Key words
lactams - radical reactions - protecting groups - cyclizations
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We have made a few attempts to effect such a cyclization but without success.
10Attempted PCC oxidation of alcohol 6 led only to the dimeric ester i. Swern oxidation led to a complex mixture (Figure). Cf [11]