What is the mechanism of amine conjugate additions to pyrazole crotonate catalyzed by thiourea catalysts?
نویسندگان
چکیده
Aminoindanol-derived thioureas catalyze proton transfer and do not stabilise anions in an asymmetric conjugate addition to pyrazole crotonate. Calculations show that the urea H-bonds play different roles in the preferred transition state and in the one leading to the minor enantiomer in the mechanism of hydroxy-thiourea catalyzed conjugate additions to pyrazole crotonates.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 7 3 شماره
صفحات -
تاریخ انتشار 2009