Tributylamine → tert-butyl 2-(3-{[tert-butyl(dimethyl)silyl]oxy)phenyl)-4-(5-chloro-2-fluorophenyl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A deoxygenated mixture of tert-butyl 3-(5-chloro-2-fluorophenyl)-2,3dihydro-1H-pyrrole-1-carboxylate (3-1, 1.100 g, 3.69 mmol, 1 equiv), tert-butyl(3-iodophenoxy)dimethylsilane (1.85 g, 5.54 mmol, 1.50 equiv), tributylamine (1.76 mL, 7.39 mmol, 2.00 equiv), triphenylarsine (0.453 g, 1.48 mmol, 0.400 equiv), and palladium acetate (0.166 g, 0.739 mmol, 0.200 equiv) in DMF (10 mL) was heated at 65° C. for 20 h. The reaction mixture was partitioned between water (100 mL) and ethyl acetate (2×85 mL). The combined organic layers were dried over sodium sulfate and concentrated. The residue was purified by flash column chromatography (100% hexanes initially, grading to 50% ethyl acetate in hexanes) to provide tert-butyl 2-(3-{[tert-butyl(dimethyl)silyl]oxy}phenyl)-4(5-chloro-2-fluorophenyl)-2,5-dihydro-1H-pyrrole-1-carboxylate (3-2) as an orange oil. 1H NMR (300 MHz, CDCl3) major rotamer: δ 7.11-6.53 (m, 7H), 6.11 (s, 1H), 5.32 (m, 1H), 4.53 (m, 2H), 1.09 (s, 9H), 0.79 (s, 9H), 0.00 (s, 6H). LRMS m/z (M+H) 504.1 found, 504.2 required.

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