Highly Selective gem-Difluoroallylation of Organoborons with Bromodifluoromethylated Alkenes Catalyzed by Palladium
摘要:
A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high alpha/gamma-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.
Highly Selective gem-Difluoroallylation of Organoborons with Bromodifluoromethylated Alkenes Catalyzed by Palladium
摘要:
A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high alpha/gamma-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.
mechanistic studies and density functional theory calculations reveal that both non‐radical and radical pathways are possible for the reaction, and the radical pathway is more likely. The high γ‐regioselectivity results from the β‐bromide elimination of alkylnickel(II) species or from the reductive elimination of nickel(III) species [(aryl)(CF2=CHCH2)NiIII(Ln)X]. The γ‐selective carbonylation of 3‐bromo‐3,3‐difluoropropene