C1-symmetric chiral bisphosphine, FcPh-Binap (1), which possesses a single diferrocenylphosphino moiety together with a conventional Ph2P-substituent, was prepared in enantiomericallypure forms. Ligand 1 is sterically less demanding than Fc-Segphos (A), which has two diferrocenylphosphino groups, and showed higher activity than A in the rhodium-catalyzed asymmetric conjugate addition of phenylboronic
Palladium-catalyzed asymmetric Heck arylation of 2,3-dihydrofuran – effect of prolinate salts
作者:Adam Morel、Ewelina Silarska、Anna M. Trzeciak、Juliusz Pernak
DOI:10.1039/c2dt31672b
日期:——
Chiral ionic liquids (CILs) containing L-prolinate and L-lactate anions and non-chiral quaternary ammonium cations were employed in the palladium catalyzed enantioselective Heckarylation of 2,3-dihydrofuran with aryl iodides (iodobenzene, 4-iodotoluene, 2-iodoanisole, 4-iodoanisole, 4-iodoacetophenone). In all the reactions 2-aryl-2,3-dihydrofuran (3) was obtained as the main product with the yield
Enantio- and Regioselective Heck-Type Reaction of Arylboronic Acids with 2,3-Dihydrofuran
作者:Liza Penn、Alina Shpruhman、Dmitri Gelman
DOI:10.1021/jo070170v
日期:2007.5.1
Reported herein is a protocol for the enantioselective Pd(II)-catalyzed Heck-typereaction between arylboronicacids and 2,3-dihydrofuran. The highest chemical and optical yields were obtained when a Pd(OAc)2/(R)-MeO(biphenylphosphine) or a Pd(OAc)2/(R)-(2,2‘-bis(diphenylphosphino)-1,1‘-binaphthyl) catalyst and a Cu(OAc)2 reoxidant were employed.
Screening of a Modular Sugar-Based Phosphite–Oxazoline Ligand Library in Asymmetric Pd-Catalyzed Heck Reactions
作者:Yvette Mata、Oscar Pàmies、Montserrat Diéguez
DOI:10.1002/chem.200601714
日期:2007.4.16
We have synthesised a library of phosphite-oxazolineligands derived from readily available D-glucosamine. These ligands have been successfully screened in the palladium-catalysed Heckreaction of several substrates with high regio- (up to 99 %) and enantioselectivities (ee's up to 99 %) as well as with improved activities under standard thermal conditions. The results indicate that the catalytic performance