One-pot tandem enantioselective hydrogenation–hydroformylation synthesis of cyclic α-amino acids
作者:Euneace Teoh、Eva M. Campi、W. Roy Jackson、Andrea J. Robinson
DOI:10.1039/b209087m
日期:2003.1.20
Five- and six-membered cyclic amino acids can be prepared in good yield with high ee (>95%)
via tandem rhodium-DuPHOS catalysed asymmetric hydrogenation followed by a rhodium-catalysed hydroformylationâcyclisation sequence in a single pot. The synthesis can be achieved using Rh-DuPHOS as the sole catalyst.
Design and synthesis of a novel three-hindered quadrant bisphosphine ligand and its application in asymmetric hydrogenation
作者:Kexuan Huang、Xiaowei Zhang、Thomas J. Emge、Guohua Hou、Bonan Cao、Xumu Zhang
DOI:10.1039/c0cc02620d
日期:——
A novel three hindered quadrant bisphosphine ligand has been synthesized. The ligand shows excellent enantioselectivities and reactivities for rhodium-catalyzed hydrogenations of various functionalized olefins.
A highly enantioselective synthesis of cyclic α-amino acids involving a one-pot, single catalyst, tandem hydrogenation–hydroformylation sequenceElectronic supplementary information (ESI) available: experimental information. See http://www.rsc.org/suppdata/cc/b2/b200374k/
作者:Euneace Teoh、Eva M. Campi、W. Roy Jackson、Andrea J. Robinson
DOI:10.1039/b200374k
日期:2002.4.19
Tandem enantioselective hydrogenation followed by a hydroformylationâcyclisation sequence leading to cyclic α-amino acids with eeâs >95% can be achieved in a single pot, one catalyst system by successive reactions of prochiral dienamide esters with H2 followed by H2/CO using Rh(I)-DuPHOS.
More electron donating, more rigid: A new highly electron‐donating P‐stereogenic bisphospholaneligand (ZhangPhos) was synthesized in a practical and highlyenantioselective manner from a commercially available chiral source. Better or comparable enantioselectivities and reactivities than TangPhos were achieved in rhodium‐catalyzed hydrogenation of various functionalized olefins (see scheme; nbd=3
Verfahren zur Herstellung von N-Acetyl-2,3-dehydro-aminocarbonsäureestern
申请人:Degussa Aktiengesellschaft
公开号:EP0076917A2
公开(公告)日:1983-04-20
Gegenstand der Erfindung ist ein Verfahren zur Herstellung von N-Acetyl-2,3-dehydro-aminocarbonsäure- estern durch Umsetzung entsprechender 2-Azido-carbonsäureester mit einem Gemisch aus einem Volumteil Essigsäureanhydrid und 1,5 bis 5 Volumteilen Essigsäure in Gegenwart von Rhenium-VII-sulfid und/oder -oxid und bei einer Temperatur zwischen 50 und 150°C, gegebenenfalls in gleichzeitiger Gegenwart von trockenem Chlorwasserstoff.