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Stereoselective vinylation of aryl N-(2-pyridylsulfonyl) aldimines with 1-alkenyl-1,1-heterobimetallic reagents.

ABSTRACT: Vinylation of aryl N-(2-pyridylsulfonyl) aldimines with versatile 1-alkenyl-1,1-borozinc heterobimetallic reagents is disclosed. In situ hydroboration of air-stable B(pin)-alkynes followed by chemoselective transmetalation with dimethylzinc and addition to aldimines provides B(pin)-substituted allylic amines in 53-93% yield in a one-pot procedure. The addition step can be followed by either B-C bond oxidation to provide ?-amino ketones (71-98% yield) or Suzuki cross-coupling to furnish trisubstituted 2-arylated (E)-allylic amines (51-73% yield).

SUBMITTER: Hussain N

PROVIDER: S-EPMC3237811 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Stereoselective vinylation of aryl N-(2-pyridylsulfonyl) aldimines with 1-alkenyl-1,1-heterobimetallic reagents.

Hussain Nusrah N Hussain Mahmud M MM Ziauddin Muhammed M Triyawatanyu Plengchat P Walsh Patrick J PJ

Organic letters 20111115 24

Vinylation of aryl N-(2-pyridylsulfonyl) aldimines with versatile 1-alkenyl-1,1-borozinc heterobimetallic reagents is disclosed. In situ hydroboration of air-stable B(pin)-alkynes followed by chemoselective transmetalation with dimethylzinc and addition to aldimines provides B(pin)-substituted allylic amines in 53-93% yield in a one-pot procedure. The addition step can be followed by either B-C bond oxidation to provide α-amino ketones (71-98% yield) or Suzuki cross-coupling to furnish trisubsti ...[more]

PMID: 22085226

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