Phenols from Allylhalides, Acetylene and Carbon Monoxide

Phenols from Allylhalides, Acetylene and Carbon Monoxide 

The above mentioned formation of methylcyclohexanone carboxylic acid, the formation of phenol and the mechanistically unsecured formation of lactones from allyl carbonyl or butyne-l-ol-4 and carbon monoxide are the only known ring closure reactions which are catalyzed by nickel catalysts. 

Phenols are also formed as by-products in low yield in the reaction of allyl chloride with acetylene and carbon monoxide in the presence of catalytic amounts of Ni(CO)4. 

Higher yields of phenol are obtained [680] if indifferent solvents are used instead of water or alcohols. 

Analogously, o-cresol is obtained from crotyl chloride and m-cresol from methallyl chloride, whereas phenylacetylene, methallyl chloride and CO yield 2-phenyl-m-cresol. Propyne, allyl chloride and CO react to give o-cresol [680, 799]. 

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