Regioselective C–H Activation Preceded by Csp2–Csp3 Reductive Elimination from Cyclometalated Platinum(IV) Complexes
摘要:
Reductive elimination reactions of the cyclometalated platinum-(IV) compounds [PtMe2Cl{C6H4CH=NCH2(4-ClC6H4)}L] and [PtMe2Br{C6H4CH=NCH2(C6H5)}L] (L = SMe2, PPh3) to form C-sp3-C-sp2 bonds, followed by either exclusive C H bond activation (L = SMe2) or competition between C-sp2-H and C-sp3-H bond activation (L = PPh3), are reported. Isomerization to give endo products instead of the expected exo complex was observed for the ligand C6H4CH=NCH2(2-BrC6H5), and formation of an endo six-membered platinacycle occurs for the ligand 2,4,6-Me3C6H2CH=NCH2(2-BrC6H4).
A one-pot synthesis of highly substituted tetrahydropyridines from N-benzylidenemethanamines, dialkyl acetylenedicarboxylates and benzylidenemalononitriles
摘要:
A simple and efficient synthesis of highly substituted tetrahydropyridines has been developed using a one-pot, two step reactions. The synthesis of a series of N-benzylidenemethanamines from benzylamines and benzaldehydes in the presence of acetic acid, followed by cyclization with dialkyl acetylenedicarboxylates and benzylidenemalononitriles, gave the corresponding tetrahydropyridines in good yields.