Zhuo-Ya Mao, Wang Chen, X. Nie
Jan 22, 2021
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Influential Citations
3
Citations
Journal
Tetrahedron
Abstract
A bstract An effective approach to access dyadic 1,3-oxazinan-2-ones 8a-8c and 4,4a,5,6-tetrahydro-[1,3]oxazino[3,4-a]quinolin-1(3H)-ones 8d-8h was developed through Sc(OTf)3-catalyzed intramolecular cyclization from tert-butoxycarbonyl to acyliminium ion 7a-7j. A variety of substituted N,O-acetals, with different ring size, proved to be suitable substrates for this transformation, and a series of (4aS,6S,7R)-6-OTBS-7-substituted-hexahydropyrrolo[1,2-c][1,3]oxazin-1-ones 11a-11j and other chiral dyadic 1,3-oxazinan-2-ones 8i, 8j, 11k were synthesized in moderate yields and with excellent diastereoselectivities (dr>99:1). Moreover, 2,5-trans-products 11a-11j were obtained through this interesting Lewis acid-catalyzed intramolecular cyclization process.