b is boron and me is methyl comprising treating a chiral boronic ester r b 2 with a methyl magnesium salt or trimethylaluminum wherein r is the same chiral organyl group and r 39 is alkyl application_number US 9105793 A description the following examples further illustrate the present invention all operations were initially carried out under a nitrogen atmosphere with oven dried glassware the spectra were obtained in an inert atmosphere the 11 b nmr spectra were recorded on a varian ft 80a spectrometer and the chemical shifts are in u03b4 relative to the ethyl etherate of boron trifluoride ee bf 3 with chemical shifts downfield from ee bf 3 assigned as positive the 1 h nmr spectra were scanned on a varian t 60 spectrometer and the 13 c nmr spectra were obtained on a varian ft 80 instrument chemical shifts all in d 2 o are relative to external me 4 si for 1 h and 13 c nmr spectra gas chromatographic analyses were carried out with a varian 1400 fid instrument equipped with a hewlett packard 3390a integrator plotter using a 6 ft u00d7 0 125 in column of 10 carbowax 20m 2 koh on chromosorb w and an internal standard capillary gas chromatographic analyses were carried.