Triethylamine → 3-[4-Methyl-3-oxo-7-trifluoromethyl-2-(2-trimethylsilanyl-ethoxymethyl)-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylmethylene]-azetidine-1-carboxylic acid tert-butyl ester

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Reaction Steps

A solution of 6-bromo-4-methyl-7-trifluoromethyl-2-(2-trimethylsilanyl-ethoxymethyl)-2,10-dihydro-9-oxa-1,2,4a-triaza-phenanthren-3-one (Example #53, Step E, 0.30 g, 0.61 mmol), 3-methylene-azetidine-1-carboxylic acid tert-butyl ester (0.123 g, 0.73 mmol), Pd(OAc)2 (0.027 g, 0.12 mmol), tri-O-tolylphosphine (0.074 g, 0.24 mmol) and triethylamine (0.184 g, 1.82 mmol) in CH3CN (10 mL) was heated at 110° C. for 14 hr. The reaction mixture was cooled to ambient temperature and the solvent was removed in vacuo. The residue was purified by preparative TLC (eluting with 25% EtOAc in petroleum ether) to give 3-[4-methyl-3-oxo-7-trifluoromethyl-2-(2-trimethylsilanyl-ethoxymethyl)-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylmethylene]-azetidine-1-carboxylic acid tert-butyl ester (0.072 g, 20%) as a yellow solid. LC/MS (Table 1, Method 2) Rt=1.523 min.; MS m/z: 605 [M+23]+.

Provenance & Evidence