Efficient and Regioselective Conversion of Epoxides into Vicinal Chloroesters with TiCl₄ and Imidazole in Ethyl Acetate

Abstract

Epoxides can be cleaved easily in EtOAc with TiCl₄ in the presence of imidazole to afford β-chloroesters with excellent yields and regioselectivity.

References

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8. The stereochemistry of the cyclic products were determined according to the following procedures: (a) the corresponding trans-halohydrins which are formed as intermediates from the reaction of epoxides with TiCl₄ in the absence of imidazole were separated and their physical data were compared with the data reported in the literature.⁹(b) The acetate or benzoate derivatives of the obtained cyclic chlorohydrins were also prepared and their physical data were compared with those reported in the literature.¹⁰(c) The spectral data obtained from the acetate derivative of halohydrins in procedure (b) were found to be identical with those obtained with our method.
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