(4-Fluoro-3-phenoxyphenyl)methyltriphenylphosphonium chloride → 1-Cyclopropyl-1-(4-chlorophenyl)-4-(4-fluoro-3-phenoxyphenyl)-1,3-butadiene

Participants

Reaction Conditions

Reaction Steps

A stirred solution of 0.71 gram (4.4 mL-0.011 mole) of n-butyllithium (2.5M in hexane) in 50 mL of dry tetrahydrofuran was cooled to -78° C., and 4.98 grams (0.01 mole) of 4-fluoro-3-phenoxyphenylmethyltriphenylphosphonium chloride (prepared in Steps C-E) was quickly added. Upon completion of addition the reaction mixture was stirred at -78° C. for one hour, and then a solution of 2.03 grams (0.01 mole) of 3-cyclopropyl-3-(4-chlorophenyl)-2-propenal (prepared in Steps A and B) in 10 mL of dry tetrahydrofuran was added dropwise during a 10 minute period. Upon completion of addition the reaction mixture was stirred at -78° C. for one hour and then was allowed to warm to ambient temperature where it was stirred for two hours. The reaction was quenched with 10 mL of aqueous dilute hydrochloric acid, and the reaction mixture was extracted with diethyl ether. The ether extract was dried with sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to a residue. The residue was subjected to column chromatography on silica gel. Elution was accomplished using 5% ethyl acetate in hexane. The appropriate fractions were combined and concentrated under reduced pressure yielding 1.4 grams of 1-cyclopropyl-1-(4-chlorophenyl)-4-(4-fluoro-3-phenoxyphenyl)-1,3-butadiene. The nmr spectrum was consistent with the proposed structure.

Provenance & Evidence