Patent ID: 8551448

Claim:
A compound having the following structure: wherein X is independently the same or different and is selected for the group consisting of O and S, X 1 is selected from the group consisting of SnMe 3 , SnBu 3 , B(—OCH 2 C(CH 3 ) 2 CH 2 O—), BF 3 K, ZnI, ZnBr, Br, Cl, F, CH 2 F, CH 2 CH 2 F, C 6 H 4 F, and CH 2 C 6 H 4 F; and X 2 is selected from the group consisting of O and S; and R is independently the same or different and is selected from the group consisting of H, lower alkyl, and a halogen; and R′ is independently the same or different and is a lower alkyl; and R″ is independently the same or different and is selected from the group consisting of H and a lower alkyl; and R 3 is independently the same or different and is selected from the group consisting of H, lower alkyl, and CH 2 F; and wherein the stereochemical configuration at any stereocenter of the compound is R, S or a mixture of these configurations.