Transition metal-catalyzed carbon-carbon bond formation promoted by organotin and organoboron reagents.

摘要

The focus of this thesis is the formation of carbon-carbon bonds catalyzed by a transition metal complex under homogeneous conditions. Two projects were examined; the first involved the addition of a reagent X-Sn (X = H, Si, Sn) using a palladium catalyst to 1,6-enynes and alkynes. 1,6-Enynes were found to cyclize to yield cyclopentyimethyl(tri-n-butyl)stannane ring systems with the combination of n-Bu₃SnH/Pd(OAc) ₂ or n-Bu₃SnSiMe₃/PdL (L = phosphine or carbene ligand). A palladium-isonitrile complex [PdCl₂( t-BuNC)₂] was found to bis(stannylate) alkynes with hexaalkylditins under mild conditions to give Z-1,2-bis(stannyi)alkenes in good to excellent yields.; The second project dealt with the coupling of bifunctional arylboronate esters with strained olefins using a rhodium catalyst in aqueous media. Through the use of a water-soluble ligand (t-Bu-AMPHOS Cl) which stabilized intermediate organorhodium species in water, functionalized indane products could be synthesized in high yield and with excellent diastereoselecitivity. The same catalyst system could be used to form Heck products from arylboronic acids and activated alkenes in high yields.