Trimethylsilylacetylene → HCID 86661615, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of bromide 59 (see Example 21) (0.310 g, 0.873 mmol), PdCl2(PPh3)2 (33 mg, 0.047 mmol) and copper iodide (18 mg, 0.095 mmol) in DMF (4 mL) and Et3N (4 mL) was purged with N2. Ethynyltrimethylsilane (0.61 mL, 4.3 mmol) was added and the mixture was stirred in a sealed tube at 50° C. for 18 h, and then partitioned between EtOAc and water. The residue was dissolved in THF (20 mL), cooled to 0° C. and treated with TBAF (1M in THF, 1.8 mL), and then the solution was stirred for 2 h. Removal of the solvent gave a residue which was partitioned between EtOAc and water. Column chromatography of the organic portion on silica gel using gradient elution (0-5% MeOH:EtOAc) gave (6S)-6-[(5-ethynyl-2-pyridinyl)methoxy]-2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine (97) (0.178 g, 68%) as a tan solid: mp 135-136° C.; 1H NMR [(CD3)2SO] δ 8.61 (d, J=1.6 Hz, 1H), 8.02 (s, 1H), 7.90 (dd, J=8.0, 2.2 Hz, 1H), 7.38 (d, J=8.0 Hz, 1H), 4.78 (d, J=13.8 Hz, 1H), 4.74 (d, J=13.8 Hz, 1H), 4.69 (dt, J=12.0, 2.6 Hz, 1H), 4.49 (d, J=12.0 Hz, 1H), 4.40 (s, 1H), 4.30-4.35 (m, 2H), 4.25 (dd, J=13.7, 3.5 Hz, 1H). Anal. (C14H12N4O4) C, H, N.

Provenance & Evidence