Chiral styrene oxides from α-haloacetophenones using NaBH 4 and TarB-NO 2, a chiral Lewis acid
DB Cordes, TJ Kwong, KA Morgan, B Singaram
Index: Cordes, David B.; Kwong, Tracey J.; Morgan, Kellie A.; Singaram, Bakthan Tetrahedron Letters, 2006 , vol. 47, # 3 p. 349 - 351
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Citation Number: 15
Abstract
High enantioselectivities are obtained for the preparation of chiral styrene oxides through reduction of α-haloacetophenones using TarB-NO2 reagent and the inexpensive and mild reducing agent NaBH4. The epoxides are easily obtained in up to 95% ee through routine acid–base workup of the product alcohols. Either the (R) or (S) epoxide can be obtained by using the appropriate l-or d-tartaric acid starting material in the TarB-NO2 reagent.
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