The effect of pressure on the diastereoselectivity of the reaction of prenal with alkyl hydrogen ylidenemalonates catalysed by homochiral secondary amines
P. Serebryakov, Edward; A. Nigmatov, Albert; A. Shcherbakov, Mikhail
Журнал:
Mendeleev Communications
Дата:
2001
Аннотация:
The dienamine-mediated formation of 6-substituted cyclohexa-1,3-dienes from the title reactants catalysed by either (S)- or (R)-prolinol at 8 kbar proceeds with different net enantioselectivities depending on the structure of RCH=C(CO2H)CO2Alk to give a product with the same configuration as that obtained at atmospheric pressure (if R = Me2C=CH) or with a configuration opposite to the latter (if R = Ph); by contrast, with both dienophiles the sense of enantioselectivity does not change with pressure when (S)-α,α-diphenyl-2-pyrrolidinemethanol is used as the catalyst.
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