Addition and coupling reactions of boron-substituted carbanions

4 Addition and coupling reactions of boron-substituted carbanions 

The boron-Wittig reaction has been carried out by bis(boryl)methyllithium 309 generated in situ from tris(boryl)-methane 308 (Equation (91 )).469 The geminal dichromium reagent 3 12470 was found to be an excellent alternative yielding 1-alkenylboronic esters 313470-472 with high //w/ -selectivity (Equation (92)). 

A treatment of 314 with LDA yielded a carbanion stabilized by boron and sulfur atom, which undergoes alkylation with organic halides and with methyl acrylate (Equation (93)).473 

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