Diethyl acetylenedicarboxylate → HCID 59000764, compound

Participants

Reaction Steps

A solution of 4-(5-phenylpyridazin-3-yl)morpholine (150 mg, 0.622 mmol) and methanesulfonic acid cyclopentylmethyl ester (Newcomb et al. (1980) J. Org. Chem. 45:1707-1708) (890 mg, 4.99 mmol) in CH3CN (30 mL) was heated at reflux for 48 h. The solvent was removed in vacuo to provide a brown oil. Diethyl acetylenedicarboxylate (150 μL, 0.933 mmol) and a 1M solution of TBAF in THF (684 μL, 0.684 mmol) were added to a solution of this oil in THF (30 mL) and EtOH (5 mL). The reaction mixture was heated at reflux for 20 h. The solvent was removed in vacuo and the residue was purified by flash chromatography (silica gel, 15% EtOAc/hexane). The resulting residue was triturated in 1:1 Et2O/hexane to provide the title compound as an off-white solid. 1H NMR (DMSO-d6) δ 0.86 (t, J=7.1 Hz, 3H), 1.17 (t, J=7.1 Hz, 3H), 1.66 (m, 2H), 1.76 (m, 2H), 1.87 (m, 2H), 2.23 (m, 2H), 3.48 (m, 6H), 3.72 (m, 4H), 4.06 (m, 1H), 4.15 (q, J=7.1 Hz, 2H), 6.77 (s, 1H), 7.39 (m, 2H), 7.45 (m, 3H). Mass Spectrum (ESI+) m/e=492.3 (M+H).

Provenance & Evidence