Enones Lewis base catalysis

In a related manner, N-acylated P-amino enones experienced reductive cycliza-tion under the catalysis of a chiral Lewis base to preferentially furnish enantioen-riched 4H-l,3-oxazines, where trichlorosilane acted not only as a reductant but also as a dehydrating agent [35], The selectivity of 9 was revealed to be superior to that of SEGPHOS-derived 10 (Scheme 7.20). 

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