Acetaldehyde → HCID 19735971, compound

Participants

Reaction Steps

Zinc chloride (524 mg) was fused in vacuo and, after cooling, treated with 4-(benzyloxycarbonyl)benzoyl chloride (21.48 g, 78.2 mmole). After 30 min., acetaldehyde (3.44 g, 78 mmole) was added at 0° C. The reaction mixture was stirred at room temperature for 30 min. and then diluted with CH2Cl2. The mixture was stirred for another 30 min. and then washed with water (3×). After drying with MgSO4, filtration, and concentration in vacuo, a green/brown solid was obtained that was chromatographed (25:75-CH2Cl2 :hexane) to give 7.65 (31%) of 1-chloroethyl 4-(benzyloxycarbonyl)benzoate as a white solid: mp 79°-82° C.; Anal. calcd for C17H15CIO4 ; C, 64.06; H, 4.74. Found: C, 63.88; H, 4.44. This chloroethyl ester (4.00 g, 12.5 mmole) was combined with the sodium salt of 3-[hydroxy-(2-thienyl)methylene]-6-chloro-5-fluoro- 2,3-dihydro-2-oxo-1H-indole-1-carboxamide (4.51 g, 12.5 mmole) and sodium iodide (644 mg, 4.3 mmole) in acetone (40 ml) and refluxed for 12 hr. The reaction mixture was filtered and the filtrate concentrated in vacuo. The orange/brown gum was chromatographed (25:75-EtOAc: hexane, then 1:99-EtOAc:CH2Cl2) to give 1.947 g (25%) of an orange foam: Anal. calcd. for C31H22ClFN2O7S·2/3H2O: C, 58.81; H, 3.72; N, 4.43. Found: C, 58.74; H, 3.38; N, 4.38.

Provenance & Evidence