1H-Pyrrolo(2,3-b)pyridine → Tert-butyl 4-(1H-pyrrolo[2,3-B]pyridin-3-YL)-5,6-dihydropyridine-1(2H)-carboxylate

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Reaction Steps

1H-Pyrrolo[2,3-b]pyridine (3 g, 25 mmol), 4-oxo-piperidine-1-carboxylic acid tert-butyl ester (4.2 g, 21 mmol) and potassium hydroxide (3.56 g, 63 mmol) were added in MeOH (60 mL) and heated to reflux for 16 h. The reaction mixture was then cooled to room temperature and poured into ice water (300 mL). The mixture was extracted with 10% MeOH/CH2Cl2 (5×150 mL). The organic extracts was dried over Na2SO4 and concentrated to form a solid. The solid was washed with MeOH (150 mL), filtered and dried to give a light yellow solid 5.7 g (91%). TLC (silica, 50% EtOAc/hexanes): Rf=0.3. MS (electrospray): exact mass calculated for C17H21N3O2, 299.16; m/z found, 300.2 [M++H]. 1H NMR (CDCl3, 400 MHz) 10.97 (br s, 1H), 8.33 (dd, J=3.33 Hz, 1.37 Hz, 1H), 8.20 (dd, J=6.65 Hz, 1.37 Hz, 1H), 7.34 (br s, 1H), 7.25 (s, 1H), 7.13 (dd, J=4.89 Hz, 3.13 Hz, 1H), 4.14 (br s, 2H), 3.68 (t, J=5.28 Hz, 2H), 2.56 (br s, 2H), 1.49 (s, 9H).

Provenance & Evidence