RESUMO
The highly regio- and stereoselective hydrosilylation of internal alkynes with silylborate catalyzed by Cu(OTf)2 with 1,10-phenanthroline as the ligand in the presence of Cs2CO3 in water is developed. This protocol was applied efficiently in the aqueous synthesis of multi-substituted vinylsilanes.
RESUMO
An efficient cooperative biscinchona alkaloid and Lewis acid catalytic system was developed in the enantioselective α-alkylation of 2-oxindoles with (3-indolyl)(phenyl)methanols to provide (2-oxindole)-linker-indole derivatives in good yields (70-83%) with high enantioselectivities (81%-92%).
Assuntos
Alcaloides/química , Indóis/química , Ácidos de Lewis/química , Metanol/química , Catálise , Metanol/análogos & derivados , Estrutura Molecular , Oxindóis , EstereoisomerismoRESUMO
The reaction of Morita-Baylis-Hillman (MBH) alcohols with Me2PhSiBpin under the catalysis of Cu(OTf)2/pyridine in methanol has been developed. The direct silylation of allylic alcohols via dual activation of the Si-B bond and the hydroxyl group of the MBH alcohol provides an efficient and convenient method for the synthesis of functionalized allylsilanes.
Assuntos
Álcoois/química , Mesilatos/química , Silanos/química , Silanos/síntese química , Catálise , Estrutura Molecular , EstereoisomerismoRESUMO
An enantioselective [3+2] annulation of Morita-Baylis-Hillman carbonates with trifluoropyruvate catalyzed by modified cinchona alkaloids was developed in good to excellent yields with excellent diastereo- and enantioselectivities.
Assuntos
Aminas/química , Carbonatos/química , Isatina/química , Ácido Pirúvico/química , Catálise , Estereoisomerismo , Especificidade por SubstratoRESUMO
A direct dehydrative coupling of terminal alkynes with allylic alcohols catalyzed by Pd(PPh3)4 with an N,P-ligand assisted by Ti(OiPr)4 has been developed. The coupling reaction tolerates various functional groups, providing a valuable synthetic tool to access 1,4-enynes.