4-Amino-1-allenylsilanes from 4-Aminopropargylic Acetates through a Silylzincation/Elimination Sequence
Received: 24 March 2016
Accepted after revision: 18 April 2016
13 June 2016 (online)
In memory to Professor Jean Normant for his outstanding contribution to organometallic chemistry
4-Aminopropargylic acetates afford 4-amino-1-allenylsilanes upon reaction with the lithium (triorganosilyl)zincate (PhMe2Si)3ZnLi. The reaction is both stereoselective and stereospecific and proceeds through syn-silylzincation of the carbon–carbon triple bond followed by subsequent anti-β-elimination of the acetate group.
- 1 Current address: ESPCI ParisTech, PSL Research University, Laboratoire de Chimie Organique, UMR CNRS 8231, 10 rue Vauquelin, 75231 Paris Cedex 05, France.
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For examples, see:
The study has been undertaken with racemic α-N-tert-butanesulfinamidoalkyl methoxymethyl ethers 2; however these compounds can also be prepared in enantiomerically pure form. For relevant references, see:
The syn-silylzincation of terminal alkynes promoted by transition-metal catalysts has been shown to give pure E-vinylsilanes upon hydrolysis; see: