Boron metal-free conjugate

Lee K, Zhugralin AR, Hoveyda AH. Efficient C—B bond formation promoted by N-heterocychc carbenes synthesis of tertiary and quaternary B-substituted carbons through metal-free catalytic boron conjugate additions to cyclic and acyclic a,p-unsaturated carbonyls. J Am Chem Soc. 2009 131 7253-7255. 

Wu H, Radomkit S, O Brien JM, Hoveyda AH. Metal-free catalytic enantioselective C—B bond formation (pinacolato)boron conjugate additions to a,p-unsaturated ketones, esters, Weinreb amides, and aldehydes promoted by chiral N-heterocychc carbenes. J Am Chem Soc. 2012 134 8277-8285. 

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