Cycloruthenated primary and secondary amines as efficient catalyst precursors for asymmetric transfer hydrogenation.
نویسندگان
چکیده
[reaction: see text] Ruthenacycles obtained by cyclometalation of enantiopure aromatic primary or secondary amines with [(eta6-benzene)RuCl2]2 or with [(eta6-p-cymene)RuCl2]2 are efficient catalysts for asymmetric transfer hydrogenation (TOF up to 190 h(-1) at room temperature). Enantioselectivities in the transfer hydrogenation of acetophenone ranged from 38% to 89%. It is possible to prepare the catalysts in situ, which allows the use of high throughput experimentation.
منابع مشابه
Cycloruthenated compounds as efficient catalyst for asymmetric hydride transfer reaction*
Cycloruthenated complexes obtained by direct C–H activation of enantiopure aromatic primary and secondary amines are efficient catalysts in asymmetric hydride transfer reaction. Reduction of acetophenone has been achieved rapidly with enantiomeric excesses (ee’s) ranging from 38 to 89 %. The importance of Ru–C bond in the catalytic efficiency is highlighted.
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ورودعنوان ژورنال:
- Organic letters
دوره 7 7 شماره
صفحات -
تاریخ انتشار 2005