2-butadiynyl-2-adamantol

Adamantane (1g, 3.35mMol) in 100ml dry ether were added dropwise to a suspension of 1,4-dichlorobutyne (1.55g, 12.6mMol) in a blue solution of sodiumamide (1.34g Na = 3.8mMol in 200ml liquid ammonia) under nitrogen. The reaction mixture was kept at -78oC for 8h before slowly allowing to reach roomtemperature while constantly replacing the evaporating ammonia with 200ml dry ether. The suspension was then stirred for another 6h before acid work-up. Three spots could be separated on TLC using ether/hexane/petrol=1:1:1; The spot with RF=0.5 could be isolated as a white solid and identified as 2-butadiynyl-2-adamantol 6, m.p. 98-101oC. MS m/z 218 (M+NH4+), 200 (M+NH4-H20)+, 183 (M+-H20); IR (nujol) 3496.9 (O-H), 3297.6 (C[[equivalence]]C-H) cm-1; 1H-NMR δ 2.2 (S, 1Η: diacetylenic proton), δ 1.5-2.2ppm (15H: adamantyl-scaffold). Crystals of 6 suitable for X-ray analysis were grown in CHCl3.