This program in organoboron chemistry is being supported by the Organic and Macromolecular Chemistry Program. The vast majority of molecules in natural systems exist in only a right- or left-handed form. This phenomenon was discovered by Pasteur. This work will develop new routes to these right- or left-handed forms using organoboron compounds as reagents. These organoboron compounds are being developed as synthetic tools to facilitate new and economic pathways to the complex molecules that occur in nature. The hydroboration reaction makes organoboranes readily available. Research in this area has extended the applicability to the synthesis of cyclic, polycyclic and various partially alkylated organoboranes. A recently developed method of enhancing the optical purity of mono- and diisopinocompheylalkylboranes to essentially 100% enantiomerically pure boronic esters opens possibilities for preparing a variety of chiral boranes in essentially 100% enantiomeric purity. The reactions of organoboranes commonly proceed with complete retention. For the first time, it is possible to develop a procedure for the synthesis of optically pure enantiomers. To explore this possibility, it is planned to search for new reactions leading to valuable compounds not now available, such as terminal acetylenes, mercaptans, nitriles, etc. A systematic study will be made to modify certain existing reactions to accommodate relatively hindered optically active groups. The utility of various homologating agents will be explored for the homologation of boracyclanes and vinylborane derivatives. The homologation of B-alkyl-9-borabicyclo?3.3.1!nonane derivatives to alpha-amino acid derivatives will be examined. The synthesis of various stereodefined vinylorganoboranes will be made and studied for their utility in the synthesis of a wide variety of unsaturated organic compounds.
