The enantioselective benzoin condensation promoted by chiral triazolium precatalysts: stereochemical control via hydrogen bonding.
نویسندگان
چکیده
The design of a new class of triazolium ion precatalysts incorporating protic substituents is described. These materials promote the enantioselective benzoin condensation of a range of aromatic aldehydes (1-62% ee). Catalyst evaluation studies strongly support the involvement of hydrogen bond donation by the catalyst in the stereocentre-forming step of the catalytic cycle.
منابع مشابه
Highly chemoselective direct crossed aliphatic-aromatic acyloin condensations with triazolium-derived carbene catalysts.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 7 17 شماره
صفحات -
تاریخ انتشار 2009