Unsymmetrical 1

Identifier:  PC:2644

Handle: https://hdl.handle.net/20.500.11797/PC2644

Authors:  Carbó, J.J.; Cuenca, A.B.; Cid, J.; García-López, D.; Fernández, E.

Abstract:
We have experimentally proved the unsymmetrical 1,1-diboration of diazo compounds, formed in situ from aldehydes and cyclic and non-cyclic ketones, in the absence of any transition metal complex. The heterolytic cleavage of the mixed diboron reagent, Bpin-Bdan, and the formation of two geminal C-Bpin and C-Bdan bonds has been rationalised based on DFT calculations to occur via a concerted-asynchronous mechanism. Diastereoselection is attained on substituted cyclohexanones and DFT studies provide understanding on the origin of the selectivity. The alkoxide-assisted selective deborylation of Bpin from the multisubstituted sp3-carbon and generation of a Bdan stabilized carbanion, easily conducts a selective protodeboronation sequence