CBS Catalysts

2-Methyl-CBS-oxazaborolidine and o-tolyl-CBS-oxazaborolidine

Since 1987, the series of chiral oxazoborolidines known as CBS catalysts (after Corey, Bakshi, and Shibata) have been used for catalytic reduction of prochiral ketones,1 imines,2-4 and oximes5 to produce chiral alcohols, amines, and amino alcohols, respectively, in excellent yields and ee’s. We are pleased to offer both enantiomers of 2-methyl-CBS-oxazaborolidine as dry reagents, as well as 1 M solutions in toluene.

We are also pleased to offer o-tolyl-CBS-oxazaborolidine as a 0.5 M solution in toluene for your research needs. When protonated with trifluoromethanesulfonimide, these chiral oxazaborolidines generate chiral Lewis acids, which have demonstrated great utility in the enantioselective Diels–Alder reaction (Scheme 1)6.

Diels–Alder reaction

Scheme 1.Diels–Alder reaction



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Ryu DH, Corey EJ. 2003. Triflimide Activation of a Chiral Oxazaborolidine Leads to a More General Catalytic System for Enantioselective Diels?Alder Addition. J. Am. Chem. Soc.. 125(21):6388-6390.