The Organic Synthesis Program is funding the research of Dr. Herbert C. Brown to continue his pioneering development of new chiral chemistry based on organoboranes. The work will lead to the development of new methods for the stereospecific synthesis of special groupings of atoms called functional groups. These are important for the development of new efficient routes to the complex materials needed in our economy. Research on organoboranes has extended the applicability to the synthesis of cyclic, polycyclic and various partially alkylated organoboranes. The reactions of organoboranes proceed predominantly with complete retention of configuration. This development makes it highly desirable to discover new reactions leading to other valuable compounds not now available from organoboranes. The utility of various homologating agents generated in situ in the presence of an organoborane will be explored for the homologation of boracyclanes, vinyl-and alkynylboronate esters, bi- and polycyclic boracyclanes and tertiary alkylboronate esters. The synthetic utility of a new three-carbon homologation procedure will be investigated for the preparation of alpha-vinyl boronate esters, medium- and large-ring boracyclanes and as well as their conversion to the corresponding medium- and large-ring ketones, amines and ethers. New reactions will be sought that will lead to valuable compounds not now available from organoboranes, such as mercaptans, nitriles, organophosphorous compounds, etc. The synthesis of various stereodefined vinyl organoboranes and their utility in the synthesis of stereodefined dienes, enynes and gamma, delta-unsaturated ketones will also be investigated.