Student Scholars Day

Asymmetric Synthesis of Chiral Silicon

Henry Hall Atrium 10

Chiral silanes have potential as resolving agents, chiral ligands, chiral auxiliaries and in chiral polymers. We have been investigating nucleophilic asymmetric substitution using prochiral (at silicon) menthoxy silanes. We will present progress we have made towards the synthesis of asymmetric, chiral silicon molecules. Phenyl methyl dimenthoxy silane was synthesized from dichloromethylphenysilane using lithium menthoxide in good yield. Mono-substitution of the alkoxy groups by butyl lithium was studied for both enantiomers of menthol, and yielded modest enantiomeric excess. Mono-substitution of the alkoxy groups on phenyl methyl di-(-)-menthoxy silane by tert butyl lithium was also observed, and displayed high enantiomeric excess. The tert butyl phenyl methyl menthoxy silane was reduced with DIBAL-H to verify the optical rotation. These results indicate that dimenthoxy substituted silanes may be useful precursors to chiral silanes.