One-pot preparation of alkyl halides and related compounds from alkyl diphenylphosphinites

Abstract

A mild and efficient one-pot protocol for preparing alkyl halides from alcohols was developed. In the case of the synthesis of alkyl iodides and bromides, a combination of chlorodiphenylphosphine and alkali metal salt at room temperature for 30 min was utilized. Primary alcohols yielded the target product (96-100%), secondary (72%) and tertiary alcohols (18-20%), respectively. For the preparation of alkyl chlorides, chlorodiphenylphosphine at room temperature for 45 min could be used to transform primary alcohols in the highest yield (86-90%), followed by secondary (55%) and tertiary alcohols (10%), respectively. Furthermore, this disclosed methodology for the preparation of alkyl halide from alcohol was applied for a one-pot synthesis of alkyl thiocyanates and azides. The synthesis of alkyl thiocyanates could be accomplished in high yield (77-80%) via alkyl bromide from alcohols as described above, followed by the addition of ammonium thiocyanate. However, the attempts to synthesize alkyl azides from alcohol were not successful.