Tributylvinyltin → 1,1-Dibutyl-3-(1,1-dioxido-7-vinyl-4h-1,2,4-benzothiadiazin-3-yl)-6-fluoro-4-hydroxynaphthalen-2(1h)-one

Participants

Reaction Conditions

Reaction Steps

A solution of the compound of Example 20B (120 mg, 0.20 mmol), tri-(2-furyl)phosphine (5 mg, 0.020 mmol), tris-(dibenzylideneacetone)palladium (0) (9 mg, 0.010 mmol) in tetrahydrofuran (2 mL) was stirred at ambient temperature for 10 min, during which time the solution changed from a deep maroon color to pale green. The solution was treated with vinyltributylstannane (118 □L, 0.403 mmol) followed by warming at 50° C. for 1.5 h. The solution was cooled, diluted with ethyl acetate and stirred for 1 h with 1 M KF solution. The mixture was filtered through celite® and the layers separated. The organic layer was washed with saturated NaCl solution and dried over Na2SO4. Concentration in vacuo afforded an oil which was purified by flash chromatography eluting with ethyl acetate in hexane. These procedures afforded the title compound (52 mg, 52%) as a white solid. 1H NMR (300 MHz, CDCl3): δ 0.59 (m, 2 H) 0.73 (m, 6 H) 0.89 (m, 2 H) 1.15 (m, 4 H) 1.88 (m, 2 H) 2.31 (m, 2 H) 5.41 (d, J=11.03 Hz, 1 H) 5.85 (d, J=17.65 Hz, 1 H) 6.74 (dd, J=17.47, 10.85 Hz, 1 H) 7.30 (m, 2 H) 7.43 (m, 2 H) 7.68 (m, 1 H) 7.94 (m, 2 H) 16.80 (s, 1 H).

Provenance & Evidence