Preparation of cyclopropylethyne and intermediates for preparation of cyclopropylethyne
AssigneeGreat Lakes (UK) Limited
InventorsRobert Gandy, Peter John Cremins, Allan Williams Timms
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Abstract
1-chloropropylethyne is prepared by dehydrochlorination with a base of 1-chloro-1-cyclopropylethene, which is itself prepared by treating 1-cyclopropylethanone with dichlorotriarylphosphorane or dichlorotrialkylphosphorane in the presence of a base.
Claims28
A process for preparation of 1-chloro-1-cyclopropylethene comprising treating 1-cyclopropylethanone with dichlorotriarylphosphorane or dichlorotrialkylphosphorane in the presence of a base comprising a tertiary amine in an inert solvent, wherein the dichlorotriarylphosphorane is formed in situ by reaction of a triarylphosphine or triarylphosphine oxide with phosgene, and the dichlorotrialkylphosphorane is formed in situ by reaction of a trialkylphosphine or trialkylphosphine oxide with phosgene.
A process for preparing cyclopropylethyne comprising the steps of preparing 1-chloro-1-cyclopropylethene by chlorinating dichlorotriarylphosphorane or dichlorotrialkylphosphorane in the presence of a base comprising a tertiary amine in an inert solvent and dehydrochlorinating the 1-chloro-1-cyclopropylethene with a strong base in an inert solvent, wherein the dichlorotriarylphosphorane is formed in situ by reaction of a triarylphosphine or triarylphosphine oxide with phosgene, and the dichlorotrialkylphosphorane is formed in situ by reaction of a trialkylphosphine or trialkylphosphine oxide with phosgene.
Dependencies are inferred from the claim text.