2-BROMO-6-ETHOXYCARBONYLBENZOTHIAZOLE

Step 1: To a solution of tert-butyl nitrite (4.5 mL, 37.5 mmol) and copper(II) bromide (6.0 g, 27 mmol) in CH3CN(100 mL) at rt was added a mixture of ethyl 2-aminobenzo[d]thiazole-6-carboxylate (5.0 g, 22.5 mmol) in CH3CN (50mL). The reaction suspension was stirred at rt for 1 h. The resulting reaction mixture was quenched with 300 mL of 1 NHCl aqueous solution and extracted with CH2Cl2 (3x200 mL). The combined organic layers were dried over MgSO4, and concentrated under reduced pressure. The crude product was purified on a silica gel column using a mixture ofCH2Cl2-hexanes (4:1, v/v) as eluent to give ethyl 2-bromobenzo[d]thiazole-6-carboxylate as a white solid (6.2 g, 96percent).1H NMR (300 MHz, CDCl3) δ 8.54 (d, J= 1.1 Hz, 1H), 8.16 (dd, J= 1.5, 8.7 Hz, 1H), 8.02 (d, J = 8.7 Hz, 1H), 4.43 (q, J=7.2 Hz, 2H), 1.43 (t, J= 7.2 Hz, 3H). LCMS (ESI) m/z 288, 286 (M+H)+.Add a solution of commercially available ethyl 2- aminobenzothiazole-6-carboxylate (10 g, 45 mmol) in acetonitrile (40 ML) to a solution of copper (II) bromide (12 G, 54 mmol) and tert-butyl nitrite (9 mL, 75 mmol) in acetonitrile (100 mL) at room temperature under nitrogen and stir for 45 min. Dilute the mixture with 1 N HCL (300 mL) and extract with methylene chloride (3 x 300 mL). Wash the combined organic extracts with water (300 mL), dry over MGS04, filter though a plug of silica gel and remove the solvents under reduced pressure to afford ethyl 2- bromobenzothiazole-6-carboxylate (Step 1) as an off-white solid (11.5 g, 89percent): 1H NMR (CDC13) 5 1.40 (t, 3H), 4.40 (q, 2H), 8.00 (d, 1H), 8.20 (d, 1H), 8.60 (s, 1H).

Molecular Weight:286.15
XLogP3:3.6
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:3
Exact Mass:284.94591
Monoisotopic Mass:284.94591
Topological Polar Surface Area:67.4
Heavy Atom Count:15
Complexity:252
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes