tert-Butyl 4-(2-aminophenyl)-5,6-dihydropyridine-1(2H)-carboxylate synthesis

Yield:955397-70-3 82%

Reaction Conditions:

with sodium sulfide;ethanol;water at 60; for 15 h;

Steps:

15.2

Step 2 - Synthesis of Compound D0.15 g (0.50 mmol) of 4-(2-nitro-phenyl)-3,6-dihydro-2H-pyridine-1 -carboxylic acid tert-butyl ester was mixed with sodium sulfide nonahydrate (0.31 g, 1.3 mmol) EPO and a solution of EtOH/H₂O (1/1 , 2 ml_). The reaction was heated to 60 ⁰C and allowed to stir at this temperature for about 15 hours, after which time the reaction was quenched with water. The resulting solution was extracted with EtOAc/Ether (1/1 ) three times and the combined organics were washed sequentially with water and brine. Concentration of the organics in vacuo provided intermediate compound D as an oil (112 mg, 82%). ¹H NMR (400 MHz, CDCI₃) 57.10-7.06 (m, 1 H), 7.01- 6.98 (m, 1 H), 6.82-6.74 (m, 2 H), 5.82-5.74 (m, 1 H), 4.08-4.02 (m, 2H), 3.63 (t, J = 5.6 Hz, 2H), 2.44-2.38 (m, 2H), 1.49 (s, 9H). HPLC-MS RT= 1.69 minutes, mass calculated for formula Ci₆H₂₂N₂O₂ 274.17, observed LCMS m/z 297.20 (M+Na).

References:

WO2008/54702,2008,A1 Location in patent:Page/Page column 118-119