Реакция #72600

Уравнение реакции

HCl

Water

tert-butyl 4-(4-cyano-2-methylphenyl)piperazine-1-carboxylate

Water

Sodium hydroxide

sodium hydroxide

→

4-(4-(tert-butoxycarbonyl)piperazin-1-yl)-3-methylbenzoic acid

Выход 92.0%

Растворители

EtOH

Условия реакции

Обработка

1. 1
   ТемператураThe reaction mixture was cooled to 23° C.
2. 2
   Фильтрацияfiltered
3. 3
   Промывкаrinsed with H2O (3×10 mL)
4. 4
   Другоеthe resulting solid was dried in vacuo

Методика

To a suspension of tert-butyl 4-(4-cyano-2-methylphenyl)piperazine-1-carboxylate (3.685 g, 12.23 mmol) in EtOH (Volume: 50 mL) and Water (Volume: 10 mL) was added Sodium hydroxide solution (8.48 mL, 162 mmol) at 23° C. Rinsed sodium hydroxide forward with Water (Volume: 2.5 mL). The reaction was stirred at 90° C. for 10 hr. The reaction mixture was cooled to 23° C., neutralized with 3N HCl (52 mL), filtered, rinsed with H2O (3×10 mL), and the resulting solid was dried in vacuo to provide 4-(4-(tert-butoxycarbonyl)piperazin-1-yl)-3-methylbenzoic acid (3.588 g, 11.20 mmol, 92% yield) as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.42 (s, 9 H) 2.29 (s, 3 H) 2.81-2.90 (m, 4 H) 3.42-3.53 (m, 4 H) 7.05 (d, J=8.08 Hz, 1 H) 7.70-7.77 (m, 2 H) 12.61 (br. s., 1 H). ESI-MS: m/z 321.2 (M+H)+. mp=174.7-178.6° C.

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