Diisopropylethylamine → HCID 58116558, compound

Participants

Reaction Steps

To a solution of 459 mg (0.889 mmol, purity 75%, 2:1 cis/trans isomer mixture) of the carboxylic acid from Example 59A in 19 ml of N,N-dimethylformamide were added, at RT, 541 mg (1.42 mmol) of HATU and 0.45 ml (337 mg, 2.61 mmol) of N,N-diisopropylethylamine, and the mixture was stirred for 30 min. Subsequently, the mixture was admixed with 136 mg (1.30 mmol) of ethyl N′-hydroxyimidocarbamate [G. Zinner, G. Nebel, Arch. Pharm. 1970, 303, 385-390] and then stirred at room temperature overnight. The reaction solution was purified directly by means of preparative HPLC. The resulting intermediate was taken up in toluene (50 ml), admixed with 4 Å molecular sieve and stirred under reflux overnight. The reaction solution was filtered, the filtrate was concentrated under reduced pressure and the residue was purified by means of preparative HPLC. Yield: 124 mg (31% of theory)

Provenance & Evidence