Improvements in the synthesis of secondary and tertiary ethinyl-carbinols

摘要

Secondary and tertiary ethinyl carbinols are prepared by reaction of acetylenic hydrocarbons with aldehydes or ketones in presence of an alkali metal hydroxide and a solvent of the formula where R1 and R2 are alkyl groups, and R3, R4, R5 and R6 hydrogen atoms or alkyl groups. Solvents specified are ethylene glycol dibutyl or ethyl-butyl ether, and propylene glycol diethyl ether. Potassium hydroxide may be added to an excess of the solvent while cooling to 5 DEG C. or below, acetylene and the carbonyl compound then being added alternately in portions. Substituted acetylenes such as amyl or phenyl acetylene may be added mixed with the carbonyl compound. Ethylene glycol ethylbutyl ether is prepared by adding the monoethyl ether to a suspension of sodium in toluene, and then adding butyl bromide. In examples: (1) potassium hydroxide is added to ethylene glycol ethyl butyl ether to produce a gelatinous complex, acetylene and acetone added alternately and, when reaction is complete, the product saturated with CO2, and worked up to give methyl butinol and tetramethyl butine diol; (2) phenyl acetylene and acetone in the same solvent are treated with potassium hydroxide yielding 1-phenyl-3-methyl-butinol-3.