In:
Chemistry – An Asian Journal, Wiley, Vol. 3, No. 2 ( 2008-02), p. 407-412
Abstract:
Bis‐titanium chiral Lewis acids that contain two oxygen‐bridged titanium centers were successfully applied to the asymmetric 1,3‐dipolar cycloaddition of nitrones and α,β‐unsaturated aldehydes. The introduction of the diphenylmethyl group as the N substituent on the nitrones, with the aim of destabilizing the nitrone–Lewis acid complex, led to the drastic enhancement of not only the reactivity but also the enantioselectivity. By employing this approach, 1,3‐dipolar cycloadditions of nitrones and the rather unreactive methacrolein were facilitated to give cycloadducts that bear one all‐carbon quaternary center with unique regioselectivity and excellent stereoselectivity.
Type of Medium:
Online Resource
ISSN:
1861-4728
,
1861-471X
DOI:
10.1002/asia.200700344
Language:
English
Publisher:
Wiley
Publication Date:
2008
detail.hit.zdb_id:
2233006-9
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