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Further studies of intramolecular Michael reactions of nitrosoalkenes for construction of functionalized bridged ring systems.

ABSTRACT: A wide variety of stabilized carbanions have been found to participate as nucleophiles in intramolecular Michael-type conjugate additions to in situ generated nitrosoalkenes to form bridged carbocyclic systems. The vinylnitroso platforms for these cyclizations have been prepared via two key steps involving ring-closing metathesis of vinyl chlorides and regioselective conversion of vinyl chlorides to ?-chloroketones with sodium hypochlorite in glacial acetic acid/acetone. An alternative approach to preparation of some cyclization substrates has involved use of more reactive enol ethers as precursors to the requisite ?-chloroketones. A sulfonamide anion has also been found to be an effective nucleophile in this type of reaction, leading to formation of a 6-azabicyclo[3.2.1]octane.

SUBMITTER: Kumar P

PROVIDER: S-EPMC3064737 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Further studies of intramolecular Michael reactions of nitrosoalkenes for construction of functionalized bridged ring systems.

Kumar Praveen P Li Puhui P Korboukh Ilia I Wang Tony L TL Yennawar Hemant H Weinreb Steven M SM

The Journal of organic chemistry 20110228 7

A wide variety of stabilized carbanions have been found to participate as nucleophiles in intramolecular Michael-type conjugate additions to in situ generated nitrosoalkenes to form bridged carbocyclic systems. The vinylnitroso platforms for these cyclizations have been prepared via two key steps involving ring-closing metathesis of vinyl chlorides and regioselective conversion of vinyl chlorides to α-chloroketones with sodium hypochlorite in glacial acetic acid/acetone. An alternative approach ...[more]

PMID: 21361394

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