In Lewis-basic solvents, alkynyl carbons bonded to iodine have chemical shifts approximately 12-15 ppm higher in frequency than the corresponding shifts in CDCl3. We offer computational evidence that this solvent effect comes directly from polarization of the iodoalkyne triple bond. Hartree-Fock and Density Functional Theory calculations reproduce the change in chemical shift for a gas-phase complex between the iodoalkyne and dimethyl sulfoxide as Lewis base. The amount of spin-orbit coupling from the adjacent iodine does not change appreciably in the complex, according to the calculations.

Highly enantioselective and very short syntheses of the bioactive forms of estrone (3) and desogestrel (4) are described using a chiral oxazaborolidinium catalyst (2) in the key initial step. Enantiomerically pure estrone was synthesized in eight steps from the readily available starting materials diene 5 and alpha,beta-enal 6 via intermediates 8 and 9. Desogestrel was synthesized using a similar strategy from diene 5 and alpha,beta-enal 11 via intermediates 12-17. The efficient syntheses of the chiral catalyst 2 and its enantiomer are also presented.