Use of optically active cyclic N,N-dialkyl aminals in asymmetric induction.
نویسندگان
چکیده
[reaction: see text]Cyclization of the optically active ketone N,N-dialkyl aminals A affords the diastereomer B as the major product with diastereoselectivities ranging from nearly 1:1 to essentially 100:0 depending on the cyclization studied.
منابع مشابه
Catalytic asymmetric construction of tetrasubstituted carbon stereocenters by conjugate addition of dialkyl phosphine oxides to β,β-disubstituted α,β-unsaturated carbonyl compounds.
The catalytic asymmetric phospha-Michael reaction of dialkyl phosphine oxides with β,β-disubstituted α,β-unsaturated carbonyl compounds was achieved. The products bearing tetrasubstituted carbon stereocenters were obtained in high yields with excellent enantioselectivities (up to >99% ee).
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ورودعنوان ژورنال:
- Organic letters
دوره 2 17 شماره
صفحات -
تاریخ انتشار 2000