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
Enzyme‐ and Ruthenium‐Catalyzed Enantioselective Transformation of α‐Allenic Alcohols into 2,3‐Dihydrofurans
作者:Bin Yang、Can Zhu、Youai Qiu、Jan‐E. Bäckvall
DOI:10.1002/anie.201601505
日期:2016.4.25
An efficient one‐pot method for the enzyme‐ and ruthenium‐catalyzed enantioselective transformation of α‐allenicalcohols into 2,3‐dihydrofurans has been developed. The method involves an enzymatic kinetic resolution and a subsequent ruthenium‐catalyzed cycloisomerization, which provides 2,3‐dihydrofurans with excellent enantioselectivity (up to >99 % ee). A ruthenium carbene species was proposed as
开发了一种有效的一锅法,用于酶和钌催化的 α-丙二烯醇对映选择性转化为 2,3-二氢呋喃。该方法涉及酶动力学拆分和随后的钌催化环异构化,从而提供具有优异对映选择性的 2,3-二氢呋喃(高达 >99 % ee )。钌卡宾被提议作为环异构化的关键中间体。
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.
Two enantiopure fluorous phosphines have been conveniently synthesized by combining palladium-catalyzed coupling reactions of easily available binaphthyl building-blocks with the introduction of fluorous ponytails onto aromatic compounds via ether bond formation. These new fluorous chiralphosphines have been tested as ligands in metal-catalyzed asymmetric transformations, the best results being obtained
Palladium-catalyzed asymmetric arylation of 2,3-dihydrofuran: 1,8-Bis(dimethylamino)naphthalene as an efficient base
作者:Fumiyuki Ozawa、Akihiko Kubo、Tamio Hayashi
DOI:10.1016/s0040-4039(00)91654-x
日期:1992.3
Reaction of 2,3-dihydrofuran with aryl triflate (1) in the presence of a base and a palladium catalyst, generated in situ from Pd(OAc)2 and (R)-BINAP, gave (R)-2-aryl-2,3-dihydrofuran (2) and a small amount of (S)-2-aryl-2,5-dihydrofuran (3). The enantiomeric purity of major product 2 was strongly affected by the base. 1,8-Bis(dimethylamino)naphthalene (proton sponge) as a highlybasic and sterically