Trimethylsilylacetylene → HCID 86661616, compound

Participants

Reaction Steps

A mixture of iodide 43 (see Example 2C) (1.00 g, 2.49 mmol) and copper iodide (51 mg, 0.27 mmol) in DMF (10 mL) and Et3N (10 mL) was purged with N2. Ethynyltrimethylsilane (1.0 mL, 7.1 mmol) and PdCl2(PPh3)2 (93 mg, 0.13 mmol) were added and the mixture was stirred under N2 for 0.5 h. The resulting mixture was partitioned between EtOAc and water, the organic fraction was dried, and the solvent was removed. The residue was dissolved in THF (50 mL) and tetra-n-butylammonium fluoride (5 mL of a 1M solution in THF, 5 mmol) was added. The solution was stirred for 2 h and then concentrated. The residue was partitioned between EtOAc and water, and the organic fraction was dried and concentrated. Column chromatography of the residue on silca gel using gradient elution (1:1 hexanes EtOAc to EtOAc) gave (6S)-6-[(4-ethynylbenzyl)oxy]-2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine (129) (0.530 g, 71%) as a white solid: mp 162-164° C.; 1H NMR [(CD3)2SO] δ 8.01 (s, 1H), 7.45 (d, J=8.3 Hz, 2H), 7.32 (d, J=8.3 Hz, 2H), 4.62-4.71 (m, 3H), 4.47 (d, J=11.9 Hz, 1H), 4.20-4.30 (m, 3H), 4.14 (s, 1H). Anal. (C15H13N3O4) C, H, N.

Provenance & Evidence