Reaction #1772008

Reaction equation

2-(4′-Amino-3′-iodophenyl)-6-methoxy benzothiazole

BBr3

→

2-(3′-iodo-4′-aminophenyl)-6-hydroxybenzothiazole

Yield 61.1%

Solvents

CH2Cl2

CH2Cl2

Conditions

Workup

1. 1
   OtherAfter the reaction was quenched with water
2. 2
   ExtractionThe aqueous layer was extracted with ethyl acetate (3×3 mL)
3. 3
   Dryingdried over MgSO4
4. 4
   OtherThe solvent was then evaporated under reduced pressure
5. 5
   Otherthe residue was purified by preparative TLC (Hexanes:ethyl acetate=7:3)

Procedure

To a solution of 2-(4′-Amino-3′-iodophenyl)-6-methoxy benzothiazole (5) (8.0 mg, 0.02 mmol) in CH2Cl2 (2.0 mL) was injected 1 M BBr3 solution in CH2Cl2 (0.20 ml, 0.20 mmol) under N2 atmosphere. The reaction mixture was stirred at room temperature for 18 hrs. After the reaction was quenched with water, the mixture was neutralized with NaHCO3. The aqueous layer was extracted with ethyl acetate (3×3 mL). The organic layers were combined and dried over MgSO4. The solvent was then evaporated under reduced pressure and the residue was purified by preparative TLC (Hexanes:ethyl acetate=7:3) to give 2-(3′-iodo-4′-aminophenyl)-6-hydroxybenzothiazole (4.5 mg, 58%) as a brown solid. 1HNMR (300 MHz, acetone-d6) δ (ppm): 8.69 (s, 1H), 8.34 (d, J=2.0 Hz, 1H), 7.77 (dd, J1=2.0 Hz, J2=8.4 Hz, 1H), 7.76 (d, J=8.8 Hz, 1H), 7.40 (d, J=2.4 Hz, 1H), 7.02 (dd, J1=2.5 Hz, J2=8.8 Hz, 1H), 6.94 (d, J=8.5 Hz, 1H), 5.47 (br., 2H). HRMS m/z 367.9483 (M+calcd for C13H9N2OSI 367.9480).

Source