Triethylamine → 3-Ethoxy-3-oxo-2-phenylpropanoic acid

Participants

Reaction Steps

2-Phenylmalonic acid monoethyl ester was prepared following the procedure in Journal of Organic Chemistry 2000, 65, 5834-5836. 2-Phenylmalonic acid monoethyl ester (1.02 g, 5.0 mmol) was dissolved in anhydrous dichloromethane (10 mL), and oxalyl chloride (0.52 mL, 6.0 mmol) was added, followed by one drop of N,N-dimethylformamide. The reaction mixture was stirred for 30 min, then concentrated, redissolved in anhydrous dichloromethane (5 mL) and added to a solution of 6-chloro-N-2-pyridinyl-3-pyridinemethanamine (i.e. the product of Example 2, Step A) (1.1 g, 5.0 mmol) and triethyl amine (0.83 mL, 6.0 mmol) in anhydrous dichloromethane (5 mL) at 0° C. The stirred reaction mixture was allowed to warm to room temperature over 30 min. The reaction mixture was poured onto a silica gel cartridge (Bond Elute® manufactured by Varian) and purified using a gradient of 0-50% ethyl acetate/hexanes. A mixture of desired product and starting amine was isolated (1.3 g of 33 mol % recovered amine/67 mol % desired product). 2-Phenylmalonic acid monoethyl ester (0.54 g, 2.6 mmol) was dissolved in anhydrous dichloromethane (3 mL), and oxalyl chloride (0.26 mL, 3.0 mmol) was added, followed by one drop of N,N-dimethylformamide. The reaction mixture was stirred until gas evolution ceased and then concentrated, redissolved in anhydrous dichloromethane (3 mL) and added to the mixture of recovered amine and desired product isolated previously. The reaction mixture was stirred for 30 min and then concentrated, and the crude residue was chromatographed as already described to give the title compound as a solid (0.9 g).

Provenance & Evidence