β-Tosylethylhydroxylamine: Preparation and Use as a Hydroxylamine Equivalent in Amidyl Radical-Olefin Cyclizations

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

References

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7

We have made a few attempts to effect such a cyclization but without success.

10

Attempted PCC oxidation of alcohol 6 led only to the dimeric ester i. Swern oxidation led to a complex mixture (Figure). Cf [11]