反应详情

To a solution of 200 mg (556 μmol) of the compound of step 5 in DMF (5 ml) and NMM (122 μl, 1.11 mmol) was added O-[(ethoxycarbonyl)cyanomethyleneamino]-N,N,N′,N′-tetramethyluronium tetrafluoroborate (201 mg, 612 μmol), and the mixture was stirred at room temperature for 30 min. tert-Butyl 1-piperazinecarboxylate (114 mg, 612 μmol) was then added and the reaction mixture was stirred for 3 h. The mixture was quenched with water and extracted with EA. The organic layer was separated, dried over sodium sulfate, filtered, and evaporated. The residue was purified by silica gel chromatography (EA/HEP 2:5). 285 mg of the title compound were obtained.

1. additionwas then added
2. customThe mixture was quenched with water
3. extractionextracted with EA
4. customThe organic layer was separated
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. customevaporated
8. customThe residue was purified by silica gel chromatography (EA/HEP 2:5)