Fig. 5: Desymmetrization of silicon containing 1,3-diols enabled copper catalysis and mechanism study of the copper catalyzed desymmetrization step.

a The dichlorosilane could be successfully double alkylated with diboronmethane. After the hydrogen peroxide oxidation, the resulting silicon containing 1,3-diols can be desymmetrized by copper catalysis to form chiral silicon center with excellent enantioselectivity. All yields are isolated for the copper catalyzed desymmetrization step unless otherwise noted. Enantiomeric excess was determined by chiral HPLC analysis. Experiments typically run with 1.0 equiv. of silicon containing 1,3-diol, 1.5 equiv of acid chloride and 1.2 equiv. of diisopropylethylamine on 0.2 mmol scale. For deborylative 1,3-diols synthesis, see supporting information for details. b Hammett’s linear free energy relationship study c non-liner effect study of the copper catalyzed desymmetrization step.