𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Asymmetric Hydrogenation Catalyzed by (S,S)-R-BisPast;-Rh and (R,R)-R-MiniPHOS Complexes: Scope, Limitations, and Mechanism

✍ Scribed by Ilya D. Gridnev; Yoshinori Yamanoi; Natsuka Higashi; Hideyuki Tsuruta; Masaya Yasutake; Tsuneo Imamoto

Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
387 KB
Volume
343
Category
Article
ISSN
1615-4150

No coin nor oath required. For personal study only.

✦ Synopsis

A new class of chiral C 2 -symmetric bis-(trialkyl)phosphine ligands has been prepared and used in Rh(I)-catalyzed asymmetric hydrogenation reactions. The ligands, 1,2-bis(alkylmethylphosphino)ethanes 1 a±g (abbreviated as BisP*, alkyl = tbutyl, 1-adamantyl, 1-methylcyclohexyl, 1,1-diethylpropyl, cyclopentyl, cyclohexyl, isopropyl) and 1,2bis(alkylmethylphosphino)methanes 2 a±d (abbreviated as MiniPHOS, alkyl = t-butyl, cyclohexyl, isopropyl, phenyl) are prepared by a simple synthetic approach based on the air-stable phosphine-boranes. These new ligands give the corresponding Rh(I) complexes, which are effective catalytic precursors for the asymmetric hydrogenation of a representative series of dehydroamino acids and itaconic acid derivatives. Enantioselectivities observed in these hydrogenations are universally high and in many cases exceed 99%. X-Ray characterization of four precatalysts, study of the pressure effects, deuteration experiments, and characterization of the wide series of intermediates in the catalytic cycle are used for the discussion of the possible correlation between the structure of the catalysts and the outcome of the catalytic asymmetric hydrogenation.

📜 SIMILAR VOLUMES

ChemInform Abstract: Asymmetric Hydrogen
ChemInform Abstract: Asymmetric Hydrogenation Catalyzed by (S,S)-R-BisP*-Rh and (R,R)-R-MiniPHOS Complexes: Scope, Limitations, and Mechanism.
✍ Ilya D. Gridnev; Yoshinori Yamanoi; Natsuka Higashi; Hideyuki Tsuruta; Masaya Ya 📂 Article 📅 2010 🏛 John Wiley and Sons ⚖ 35 KB 👁 1 views

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v

Stereoselectivity in Reactions of Metal
Stereoselectivity in Reactions of Metal Complexes IV. Asymmetric Synthesis of (2R, 7S, 10R)- and (2R, 7R, 10R)-2, 10-diamino-5, 5, 7-trimethyl-4, 8-diazaundecanenickel (II) by Stereoselective Hydrogenation of (2R, 10R)-2, 10-diamino-5, 5, 7-trimethyl-4, 8-diaza-7-undecenenickel(II)
✍ Bruno Güntert; Saturnin Claude; Klaus Bernauer 📂 Article 📅 1975 🏛 John Wiley and Sons 🌐 German ⚖ 852 KB

## Abstract The catalytic hydrogenation of (2__R__, 10__R__)‐2, 10‐diamino‐5, 5, 7‐trimethyl‐4, 8‐diaza‐7‐undecenenickel(II) yields two products when the reaction is performed in the presence of ethylenediamine, but only one, when ethylenediamine is absent. The stereochemistry of the reaction is di

ChemInform Abstract: Rhodium Complexes o
ChemInform Abstract: Rhodium Complexes of (R)-Me-CATPHOS and (R)-(S)-JOSIPHOS: Highly Enantioselective Catalysts for the Asymmetric Hydrogenation of (E)- and (Z)-β-Aryl-β-(enamido)phosphonates.
✍ Simon Doherty; Julian G. Knight; Adam L. Bell; Shireen El-Menabawey; Christopher 📂 Article 📅 2009 🏛 John Wiley and Sons ⚖ 32 KB 👁 1 views

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v