4-Bromo-2-benzothiazolamine

White solid

(II) LiBr (1.5 eq.) was added to a solution of the product just obtained in stage (I) (5 g, 21.64 mmol) in acetic acid (50 ml) at room temperature. The reaction mixture was cooled to 0 General procedure: A mixture of aniline (0.05mol) and NHTo a mixture of 2-((2, 2-dimethyl-2, 3-dihydrobenzofuran-7-yl)oxy)acetic acid (890 mg, 4.00 mmol) and 4-(Dimethylamino)pyridine (246 mg, 2.0 mmol) was added to a stirred suspension of 4- bromo-1, 3-benzothiazol-2-amine (4.63 g, 20.2 mmol), triethylamine (2.8 mL, 20.2 mmol) and di-tert-butyl dicarbonate (9.70 g, 44.5 mmol) in DCM (100 mL) and stirred at room temperature for 17 hours. The reaction mixture was diluted with water (100 mL) and the resulting layers separated. The aqueous layer was washed with DCM (2 × 30 mL) and the extracts combined with the original organic layer, washed with 2M HCl(aq) (50 mL), dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica, petroleum ether:ethyl acetate, gradient elution from 100:0 to 70:30) to afford the desired product as an off white solid (3.97 g, 46%). This was used in next step without further purification. (0290) LC-MS (Method A): RT: 4.48 min, m/z = 427.1/429.1 [M- H]-.2.291 g (0.01 mol) of General procedure: Compound 9 (0.1mmol) added to dry CH2Cl2 (15mL) was stirred at 0C and oxalyl chloride (2.0mmol) was dripped into the mixture and stirred at the same temperature for 12h. After the reaction, the solvent and excess oxalyl chloride was evaporated under the reduced pressure, then add CHCl3. Compounds 2 (0.1mmol) and triethylamine (0.15mmol) were added to the mixture and reflux at 65C for 5h. After the reaction, the solvent was evaporated under reduced pressure, and the crude product was purified by chromatography on silica gel eluted with petroleum CH2Cl2/CH3OH (V: V=60:1) to offer the target compounds 11a-11k in good yields.

Molecular Weight:229.10
XLogP3:2.7
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:227.93568
Monoisotopic Mass:227.93568
Topological Polar Surface Area:67.2
Heavy Atom Count:11
Complexity:155
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes