Sulfuric Acid → 4-methyl-1,5-octadiyn-4(RS)-ol

Participants

Reaction Steps

To a solution consisting of 6.06 parts of magnesium, 15 parts by volume of ether and 0.06 part of mercuric chloride, stirred at room temperature in an atmosphere of nitrogen, was added 0.5 part by volume of a solution consisting of 29.74 parts of propargyl bromide and 70 parts by volume of ether. The resulting mixture was then cooled to -10° to -15° and the remaining propargyl bromide solution was slowly added over a period of 45 minutes. At the end of the addition period, stirring was continued at -10° for about 15 minutes longer. To that mixture was then added, with stirring, over a period of 45 minutes at -3° to -5°, a mixture consisting of 22 parts of 3-hexyn-2-one and 60 parts by volume of benzene. At the end of the addition period, stirring was continued for about 20 minutes at -3°, and the reaction mixture was then poured carefully into cold dilute sulfuric acid. The aqueous phase was separated, extracted with ether and the combined ether extracts were washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Vacuum distillation of the residue afforded 4-methyl-1,5-octadiyn-4(RS)-ol, characterized by infrared absorption maxima of about 3620, 3330, 2250, 1385, 1355, 1085, 940, and 770 cm.-1.

Provenance & Evidence