tl 的文章被 organic chemistry highlights 网站进行了评论

TL 的的的的 Organic Chemistry Highlights 的的的的的的的 http://www.organic-chemistry.org/Highlights/ 2006/05March.shtm Modern Methods for Asymmetric Hydrogenation of Ketones 1. Asymmetric Transfer Hydrogenation (ATH) (Tetrahedron Lett. 20 05, 46, 7341) The reduction of acetophenone (1) could be accomplished by utiliz ing [RuCl2(p-cymene)2] / ligand (a chiral amino alcohol) in water at room temperature, with quantitative conversions and moderate t o high enantioselectivity. Best results were obtained with ephedr ine hydrochloride (5 gave optimal enantioselectivity 75% ee and 9 9.3% conversion). This group found that (-)-ephedrine hydrochloride, a stable, effi cient and cost-effective ligand when combined with [RuCl2( p-cymen e)2], is an efficient catalyst system for ATH with other ketones and gave excellent yields and good enantioselectivity (up to 83% ee). O [RuCl 2 ( p-cym ene)] 2 /Ligands ( 3-6) HCO O N a /H 2 O OH * Ph N H OH Me Ph N H OH Me 3 4 Ph N H OH Me Ph N H OH Me 5 6 HCl HCl 1 2 C onv.(% ) ee(% ) 99.5 to 100 49 to 76

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TL 的文章被 Organic Chemistry Highlights 网站进行了评论. Modern Methods for Asymmetric Hydrogenation of Ketones 1. Asymmetric Transfer Hydrogenation (ATH) ( Tetrahedron Lett. 2005 , 46 , 7341). - PowerPoint PPT Presentation

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TL的文章被 Organic Chemistry Highlights网站进行了评论

http://www.organic-chemistry.org/Highlights/2006/05March.shtm

Modern Methods for Asymmetric Hydrogenation of Ketones

1. Asymmetric Transfer Hydrogenation (ATH) (Tetrahedron Lett. 2005, 46, 7341)

The reduction of acetophenone (1) could be accomplished by utilizing [RuCl2(p-cymene)2] / ligand (a chiral amino alcohol) in water at room temperature, with quantitative conversions and moderate to high enantioselectivity. Best results were obtained with ephedrine hydrochloride (5 gave optimal enantioselectivity 75% ee and 99.3% conversion).

This group found that (-)-ephedrine hydrochloride, a stable, efficient and cost-effective ligand when combined with [RuCl2(p-cymene)2], is an efficient catalyst system for ATH with other ketones

and gave excellent yields and good enantioselectivity (up to 83% ee). O

[RuCl2(p-cymene)]2 / Ligands (3-6)

HCOONa / H2O

PhNHOH

3 4

PhNHOH

5 6

HCl HCl

1 2

Conv. (%) ee(%)

99.5 to 100 49 to 76

Highlights USA