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A mild and efficient approach to enantioenriched ?-hydroxyethyl ?,?-unsaturated ?-lactams.

ABSTRACT: A straightforward approach toward enantioenriched ?-substituted ?,?-unsaturated ?-lactams is described. Although a considerable number of approches toward ?,?-unsaturated ?-lactams have been reported, there are relatively few examples of enantioenriched ?,?-disubstituted ?,?-unsaturated ?-lactams formation. The ?-stereocenter was formed by addition of allylmagnesium bromide to an N-tert-butylsulfinyl imine. The ?,?-unsaturated ?-lactam was furnished by ring-closing metathesis. Although Baylis-Hillman chemistry failed on this cyclic compound, introduction of the hydroxyethyl group prior to ring-closing metathesis was successful. A Baylis-Hillman reaction was used to introduce the substituent at the ?-position of the ?,?-unsaturated lactam.

SUBMITTER: Han SJ

PROVIDER: S-EPMC4864989 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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A mild and efficient approach to enantioenriched α-hydroxyethyl α,β-unsaturated δ-lactams.

Han Seo-Jung SJ Stoltz Brian M BM

Tetrahedron letters 20160501 21

A straightforward approach toward enantioenriched α-substituted α,β-unsaturated δ-lactams is described. Although a considerable number of approches toward α,β-unsaturated δ-lactams have been reported, there are relatively few examples of enantioenriched α,δ-disubstituted α,β-unsaturated δ-lactams formation. The δ-stereocenter was formed by addition of allylmagnesium bromide to an <i>N</i>-<i>tert</i>-butylsulfinyl imine. The α,β-unsaturated δ-lactam was furnished by ring-closing metathesis. Alth ...[more]

PMID: 27182092

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