反应详情

温度

105 °C

(+/−) Tert-butyl (3-bromo-2-chloro-5-cyanophenyl)carbamate (1.52 g, 4.58 mmol), a 3:1 mixture of methyl 1-(oxetan-3-yl) piperazine-2-carboxylate (0.688 g, 3.44 mmol) and methyl 1-methylpiperazine-2-carboxylate (0.181 g, 1.144 mmol), Pd2(dba)3 (0.420 g, 0.458 mmol), BINAP (0.285 g, 0.458 mmol), Cs2CO3 (2.240 g, 6.88 mmol), and Toluene (40 mL) were combined in a round bottom flask. The flask was evacuated and backfilled with N2 3×, and the reaction was heated at 105° C. for 18 h. The reaction was cooled to rt and an additional 0.05 eq. each of catalyst and ligand were added. The reaction vial was resealed, evacuated and backfilled with N2 3×, then heated at 105° C. for 2 h. The reaction was cooled to rt and diluted with EtOAc. The solution was filtered through celite and the filtrate concentrated in vacuo. The crude material was purified by flash column chromatography 0-5% MeOH/DCM, then repurified with 0-20% Acetone/DCM. 292 mg of pure methyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)-1-(oxetan-3-yl)piperazine-2-carboxylate was obtained, along with 592 mg of a 3:1.7 mixture of methyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)-1-(oxetan-3-yl)piperazine-2-carboxylate and methyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)-1-methylpiperazine-2-carboxylate. Estimated yields based on 1H NMR: methyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)-1-(oxetan-3-yl)piperazine-2-carboxylate (683 mg, 1.515 mmol, 44.0% yield) and methyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)-1-methylpiperazine-2-carboxylate (201 mg).

1. customwere combined in a round bottom flask
2. customThe flask was evacuated
3. temperatureThe reaction was cooled to rt
4. customThe reaction
5. customevacuated
6. temperatureheated at 105° C. for 2 h
7. temperatureThe reaction was cooled to rt
8. additiondiluted with EtOAc
9. filtrationThe solution was filtered through celite
10. concentrationthe filtrate concentrated in vacuo
11. customThe crude material was purified by flash column chromatography 0-5% MeOH/DCM
12. customrepurified with 0-20% Acetone/DCM