Potassium Carbonate → HCID 66685270, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A tube was charged with trans-cyclohexanediamine (162 mg, 1.42 mmol, 0.5 equiv), K2CO3 (783 mg, 5.67 mmol, 2.0 equiv), 3-bromo-5-phenyl-thiophene-2-carboxylic acid methyl ester (1.01 g, 3.40 mmol, 1.2 equiv), CuI (270 mg, 1.42 mmol, 0.5 equiv), (R)-3-Cyclohexyl-5-oxo-piperazine-1-carboxylic acid tert-butyl ester (800 mg, 2.83 mmol, 1.0 equiv) and 1,4-dioxane (3.0 mL). The tube was then flushed with N2 and sealed. The reaction mixtures were heated at 110° C. for 72 hours after which it was diluted with EtOAc and filtered. The filtrate was washed with 1.0 N HCl aq. solution, brine, dried (Na2SO4) and concentrated. The residue was purified by silica gel column chromatography (EtOAc/heptane, 50%) to give product (R)-3-Cyclohexyl-4-(2-methoxycarbonyl-5-phenyl-thiophen-3-yl)-5-oxo-piperazine-1-carboxylic acid tert-butyl ester 415 mg.

Herkunft & Nachweise