Stereospecific Suzuki Cross-Coupling of Alkyl α-Cyanohydrin Triflates

Abstract

Scalemic α-cyanohydrin triflates undergo Pd-catalyzed cross-coupling with aryl, heteroaryl, and vinyl boronic acids under mild conditions. Coupling proceeds with complete inversion of configuration at the stereogenic carbon. The resultant nitrile can be easily converted into a variety of alternative functional groups of value in organic synthesis and thus achieves a higher level of molecular complexity than traditional Suzuki reactions.

Nickel-Catalyzed Cross Couplings of Benzylic Ammonium Salts and Boronic Acids: Stereospecific Formation of Diarylethanes via C–N Bond Activation

“…2b-d,5 No examples of enantioselective couplings of benzylic electrophiles with boronic acids are yet known, and only a single stereospecific coupling of a benzylic α-cyanohydrin mesylate with a boronic acid partner has been reported to our knowledge. 8 …”

Copper‐Catalyzed Cross‐Coupling Reaction of Organoboron Compounds with Primary Alkyl Halides and Pseudohalides

“…The advantages of replacing Grignard reagents with organoboron reagents are well-known, including the better commercial availability of the reagents and the higher functional-group tolerance. [8] However, whereas certain complexes of Pd, [9] Ni, [10,11] and Fe [12] have been reported to be competent catalysts for the coupling of alkyl halides with organoboron compounds, until now the catalysis of such transformations by Cu complexes has not been reported. [13] Therefore, we were surprised to find that in the presence of LiOtBu as a base, CuI could efficiently catalyze the cross-coupling of aryl boronate esters with primary halides and pseudohalides containing a CÀX bond (X = I, Br, Cl, OTs, and OMs; Ts = p-toluenesulfonyl, Ms = methanesulfonyl).…”

“…It may thus complement palladium-and nickel-catalyzed Suzuki-Miyaura coupling reactions of alkyl halides. [9][10][11] We began our study by examining the coupling of ndodecyl p-toluenesulfonate with an aryl boronate ester 1. We initially used CuI as the catalyst and tested several different bases ( Finally, under the present conditions, the reaction of cyclohexyl p-toluenesulfonate with 1 gave only a trace amount of the desired product.…”

Copper‐Catalyzed Cross‐Coupling Reaction of Organoboron Compounds with Primary Alkyl Halides and Pseudohalides

“…It may thus complement palladium-and nickel-catalyzed Suzuki-Miyaura coupling reactions of alkyl halides. [9][10][11] We began our study by examining the coupling of ndodecyl p-toluenesulfonate with an aryl boronate ester 1. We initially used CuI as the catalyst and tested several different bases ( entry 29).…”