Functionalization of C-H bonds holds a great promise to fundamentally change the practice of organic synthesis and make it far more efficient. Although recent advances have begun to realize its potential, much more development will be needed especially in the area of diastereoselective functionalization of sp3 C-H bonds. This proposal details approaches about the use of a chelate group to direct Pd or Rh catalyzed activation of a sp3 C-H bond. The preexisting chirality within substrates will be used to bias the diastereoselectivity of C-H activation. The resulting diastereomerically enriched cyclometalled complexes will be explored in three types of reactions: 1) carbon-carbon formation via either Suzuki or Hiyama coupling; 2) regioselective alkylation of Pd pi-allyl complexes; 3) borylation with bis(pinacolato)diboron. The three types of reactions discussed in this proposal will serve as a platform to probe the factors about how to control diastereoselectivity in C-H functionalization of acyclic substrates. Each type of reaction can be also applied in a complementary fashion with current aldol methodologies, Pd pi-allyl chemistries, and crotylmetal technologies. ? ? ?
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