Propargyl alcohol → 2-Methoxy-6-(6-methoxy-4-(prop-2-yn-1-yloxy)benzofuran-2-yl)imidazo[2,1-b][1,3,4]thiadiazole

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Reaction Steps

A solution of 6-methoxy-2-(2-methoxyimidazo[2,1-b][1,3,4]thiadiazol-6-yl)benzofuran-4-ol (Example 1H, 205 mgs, 0.646 mmol) in THF (10 mL) was treated at r.t. and under a nitrogen atmosphere, with propargyl alcohol (0.096 mL, 1.615 mmol), tri-n-butylphosphine (0.398 mL, 1.615 mmol) and dropwise, over a 25 min period with a solution of 1,1′-(azodicarbonyl)dipiperidine (408 mgs, 1.615 mmol) in THF (10 mL). The mixture was sonicated in a bath for 30 min and stirred at r.t. for another 30 min. The mixture was then dissolved in dichloromethane (50 mL) and washed with sat. aqueous NaHCO3, brine and dried (MgSO4). Evaporation of the solvent gave a solid that was purified by silica gel column chromatography ISCO to give the title material (180 mg, 0.507 mmol, 78% yield). 1H NMR (DMSO-d6, 400 MHz) δ ppm: 8.38 (s, 1H), 6.92 (s, 1H), 6.86 (dd, J=1.8, 1.0 Hz, 1H), 6.53 (d, J=1.6 Hz, 1H), 4.94 (d, J=2.7 Hz, 2H), 4.21 (s, 3H), 3.77-3.84 (m, 3H), 3.60-3.66 (m, 1H).

Provenance & Evidence