ethyl 2-(6-bromoH-imidazo[1,2-a]pyridin-3-yl)acetate

General procedure: To a 5 mL Schlenk tube were added aryl / heteroaryl acetates 3 (1.0 mmol, 1.0 equiv.), vinyl diphenylsulfonium triflate (434.4 mg, 1.2 mmol, 1.2 equiv.) and DMSO (5 mL). The mixture was stirred at room temperature for 2 min and to the mixture was added DBU (456 mg, 3 mmol, 3.0 equiv.). The mixture was stirred for 12 hours at room temperature till the reaction was complete. To the resulting mixture was added saturated ammonium chloride solution (25 mL), and the mixture was then extracted with EtOAc (3 x 150 mL). The combined organic layers were washed with H2O (2 x 30 mL), dried with anhydrous sodium sulfate. After concentration, product 4 was purified using column chromatography on silica gel using an appropriate eluent.Reflux a solution of 4, 4-dimethoxy-but-2-enoic acid ethyl ester (3.3 g, 19.12 mmol) and toluene-4-sulfonic acid (0.02 g, 0.12 mmol) in a solution of 2: 1 acetonitrile: water (90 mL) for 30 min. Add 2-AMINO-5-BROMO-PYRIDINE (1.65 g, 9.56 mmol) and reflux for 15 h. Cool and concentrate TO-20 ML. Dilute the reaction with saturated aqueous sodium bicarbonate and extract into ethyl acetate. Combine and concentrate organic extracts. Flash chromatography using ethyl acetate/dichloromethane/methanol mixtures gives the subtitled compound as a brown oil (2. 9 G). TOF MS ES+ exact mass calculated for CLLHNBRN202 (P+1) : m/z = 283.0075 Found: 283. 0082. 1H NMR (400 MHz, DMSO-d6) B 8.68 (s, 1H), 7.55 (d, J = 10 Hz, 1H), 7.49 (s, 1H), 7.34 (d, J = 10 Hz, 1H), 4.15 (s, 2H), 4.09 (q, J = 4 Hz, 2H), 1.18 (t, J = 4 Hz, 3H). EA Calcd. For CLLHLLBRN202 : C, 46.66 ; H, 3.92 ; N, 9.89 ; Found C, 46.56 ; H, 4.02 ; N, 9.60.Preparation 178; 2-(6-ethylimidazo [1, 2-a] pyridin-3-yl) acetamide; Ethyl 2- (6-vinylimidazopyridinf 1, 2-alpyridin-3-yl) acetate; Bubble nitrogen into a mixture of ethyl 2- (6-bromoimidazo [1, 2-a] pyridin-3-yl)- acetate (2.0 g, 7.0 mmol), vinyltributyltin (3.3 g, 11 mmol) and tetrakis (triphenyl- phosphine) Pd (0) (0.25 mg) in a resealable tube in toluene for 3 minutes. Heat and stir at 110°C for 16 hours. Cool and concentrate under reduced pressure. Subject the residue to silica gel chromatography, eluting with hexane/ethyl acetate; 1: 1 to 0: 1 provide the desired compound (0.90 g, 55percent). MS (ES): m/z = 231 (M++H).Add 0. 5M diisobutylaluminum hydride in toluene (4.6 mL, 2.29 mmol) to a solution of (6-bromo-imidazo [1, 2-a] pyridin-3-yl) -acetic acid ethyl ester (0.65 g, 2.29 mmol) and morpholine (5 mL) in THF (40 mL) AT-78 C. Gently warm the reaction to room temperature and dilute carefully with methanol. Filter and concentrate the filtrate. Flash chromatography gives the subtitled compound (0.24 g, 32percent) as a white solid. MS ES+m/e 324.0, 326.0 (M+1).

Molecular Weight:283.12
XLogP3:2.6
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:4
Exact Mass:282.00039
Monoisotopic Mass:282.00039
Topological Polar Surface Area:43.6
Heavy Atom Count:16
Complexity:262
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes