Kuraray Co., Ltd.

Toshimichi Mitani

Manzo Shiono

Goro Asanuma

Tatsuhiko Hayashibara

Yoshihisa Tsuji

Makoto Nakazawa

Shigeo Oozono

Yoichi Satake

Steroid derivatives useful as intermediates for producing vitamin D derivates as well as processes for producing the steroid derivatives are provided. The steroid derivatives include halide compounds represented by the following formulae:

Processes for the preparation of steroid derivatives, intermediates therefor and processes for the preparation of the intermediates

A method for producing bromomethylcyclopropane is provided, comprising reacting an organic sulfonyl halide with cyclopropylmethanol in the presence of a tertiary amine in a non-protic solvent, to generate cyclopropylmethyl organic sulfonate, and reacting the resulting cyclopropylmethyl organic sulfonate with an alkali metal bromide and/or a quaternary ammonium bromide in a non-protic polar solvent.

Method for producing bromomethylcyclopropane

According to the present invention, a process for the preparation of a cyclopropylacetylene derivative represented by the following formula (III): ##STR1## is provided, which comprises reacting a cyclopropylacrylic acid derivative represented by the following formula (I): ##STR2## with a halogenating agent to obtain a halogenocyclopropylpropionic acid derivative represented by the following formula (II): ##STR3## and reacting the halogenocyclopropylpropionic acid derivative with a base.

Process for the preparation of cyclopropylacetylene derivatives

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Kurashiki, Japan

Toshimichi Mitani