Triethylamine → HCID 69432606, compound

Benzyl 2-benzyl-4-{2-[(3-nitrophenyl)amino]-2-oxoethyl}piperazine-1-carboxylate. To a solution of 3.0 g (10.9 mmol) of (RS)-tert-butyl 2-benzylpiperazine-1-carboxylate in 30 mL of methylene chloride at 0° C. was added 2.3 mL (16.5 mmol) of triethylamine and 1.7 mL (11.9 mmol) of benzyl chloroformate. The resultant mixture was stirred at ambient temperature for 16 h and an additional 0.4 mL (2.8 mmol) of benzyl chloroformate was added. After stirring for a further 2 h, the reaction was partitioned between methylene chloride and water. The organic layer was washed sequentially with dilute hydrochloric acid, saturated sodium bicarbonate solution, and brine, dried over magnesium sulfate, and concentrated in vacuo to give 4-benzyl 1-tert-butyl 2-benzylpiperazine-1,4-dicarboxylate. The tert butyl carbamate was deprotected as described in Example 1, Step A to give 2.9 g of the free amine. A portion (1.5 g, 4.8 mmol), of this material was coupled with 1.6 g (7.5 mmol) of alpha-chloro-3-nitroacetanilide as described in Example 1, Step A, to give 1.3 g of the title compound as an off-white foamy solid. 1H NMR (400 MHz, CD3OD) δ 8.70 (s, 1H), 7.99 (d, 1H, J=8 Hz), 7.96 (d, 1H, J=8 Hz), 5.58 (t, 1H, J=8 Hz), 7.36–7.05 (m, 10H), 5.00 (bs, 2H), 4.38–4.31 (m, 1H), 3.99 (d, 1H, J=16 Hz), 3.48 (td, 1H, J=16,2 Hz), 3.22–2.95 (m, 5H), 2.80 (d, 1H, J=14 Hz), 2.33–2.20 (m, 2H).

1. customthe reaction was partitioned between methylene chloride and water
2. washThe organic layer was washed sequentially with dilute hydrochloric acid, saturated sodium bicarbonate solution, and brine
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo

ORD record

ord-82846a3e896d4b4494fe26e34a6de149

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07253172B2