1,1,3,3-Tetramethylguanidine → HCID 68466355, compound

Participants

Reaction Conditions

Reaction Steps

A solution of N-(benzyloxycarbonyl)-α-phosphonoglycine trimethyl ester (5.50 g, 16.6 mmol) and tetramethylguanidine (1.99 mL, 15.9 mmol) in anhydrous tetrahydrofuran (50 mL) was stirred at −78° C. for 20 min. To this was added a solution of 5-formyl-indazole-1-carboxylic acid tert-butyl ester (3.72 g, 15.1 mmol) in tetrahydrofuran (25 mL) slowly via syringe over 10 min. The reaction mixture was stirred at −78° C. for 4 h and then allowed to warm to room temperature overnight. The solvent was evaporated and the resulting residue subjected to flash column chromatography on silica gel (1:2 ethyl acetate/hexane) giving the title compound as a white foam (5.77 g, 85%). 1H-NMR (CDCl3, 500 MHz) δ 8.09 (d, J=9.0 Hz, 1H), 8.08 (s, 1H), 7.84 (s, 1H), 7.67 (d, J=9.0 Hz, 1H), 7.47 (s, 1H), 7.30 (br s, 5H), 6.43 (br s, 1H), 5.09 (s, 2H), 3.84 (s, 3H), 1.72 (s, 9H). Mass spec.: 452 (MH)+.

Provenance & Evidence