Sodium Cyanide → 5-Heptynenitrile, 7-hydroxy-

To a stirred slurry of sodium cyanide (15 g, 306 mmol) in dimethyl sulphoxide (100 ml) preheated to 85° C., was added 1-tetrahydropyranyloxy-6-chloro-hex-2-yne (66.2 g, 306 mmol) at such a rate as to keep the temperature between 85° C. and 100° C. One hour after the addition was completed, the cooled mixture was slowly added to brine (600 ml) and extracted with ether (3×200 ml). The combined ether extracts were washed with further brine (200 ml) and dried over sodium sulphate. After removal of the solvent under reduced pressure, the reddish-brown oil was distilled and the fraction boiling between 140° and 160° C. (0.25 m.m.) collected and dissolved in methanol (200 ml). This solution was stirred overnight with 5 MH2SO4 (30 ml) and neutralised with solid potassium carbonate. The methanol was removed under reduced pressure and the residue partitioned between ether (200 ml) and brine (300 ml). The aqueous layer was extracted with further ether (2×300 ml). The combined organic extracts were washed with brine (2×100 ml) and dried over sodium sulphate. Removal of the solvent under reduced pressure, and distillation of the oil obtained gave 6-cyano-hex-2-yn-1-ol (22.0 g, 58%) as a colourless oil.