Hexane → 4-[2-(4-Chloro-phenyl)-6-oxo-4-thioxo-6H-1-oxa-3b,5-diaza-cyclopenta[a]pentalen-5-yl]-N-(3-dimethylamino-propyl)-3,3-dimethyl-butyramide

Participants

Reaction Conditions

Reaction Steps

Compound 11 (105 mg, 0.25 mmol) was dissolved in dichloromethane (5 ml) and 3-hydroxy-dihydrobenzotriazinone (HODhbt, 49 mg, 0.3 mmol, 1.2 molequivalents) was added thereto, followed by addition of Et3N (51 mg, 0.5 mmol, 2 molequivalents) and 4-dimethylaminopyridine (DMAP, 15 mg, 0.125 mmol, 0.5 molequivalents). The mixture was stirred at 25° C. for 16 hours while being monitored by TLC, using a 6:4 hexane:ethyl acetate mixture as eluent, until the appearance of a less polar spot of the active ester intermediate was observed. The solvent was then evaporated under reduced pressure and the residue was dissolved in chloroform (10 ml). N,N-dimethylaminopropylamine (DMAPA, 103 mg, 1 mmol, 2 molequivalents) was then added and the active ester was consumed after additional 1 hour, as indicated by TLC. Chloroform was thereafter added and the mixture was washed three times with 5% NaHCO3, with 1 M HCl, dried (Na2SO4) and the solvent was evaporated under reduced pressure to give a red solid. Chromatography was carried out using a 88:10:2 EtOAc:MeOH:Et3N mixture as eluent to give Compound 15 (101 mg, 69% yield) as a red solid.

Provenance & Evidence