Methyl iodide → 5-Bromo-2-(methylthio)benzo[d]thiazole

HRID 1972985Notes

Reaction equation

HRID 1972985 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[S:9][C:8]([SH:10])=[N:7][C:6]=2[CH:11]=1.[CH2:12]1COCC1.IC.[OH-].[K+]>[Br-].C([N+](CCCC)(CCCC)CCCC)CCC.CCOC(C)=O>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[S:9][C:8]([S:10][CH3:12])=[N:7][C:6]=2[CH:11]=1

Participants

7

Reactant 4

HCID 6328Methyl iodideHCID 8028TetrahydrofuranHCID 14797Potassium HydroxideHCID 178527757HCID 178527757, compound

Product 1

HCID 28012715-Bromo-2-(methylthio)benzo[d]thiazoleYield 76%

Reagents, catalysts & solvents 2

HCID 74236Tetrabutylammonium BromideCatalystHCID 8857Ethyl AcetateSolvent

Procedure

A mixture of 5-bromo-1,3-benzothiazole-2-thiol (3.0 g, 12.19 mmol), dry THF (44 mL), iodomethane (0.80 mL, 12.80 mmol), KOH (0.68 g, 12.19 mmol), and tetra-n-butylammonium bromide (0.39 g, 1.2 mmol) was stirred at rt overnight. The reaction mixture was diluted with EtOAc (100 mL) and washed with saturated, aqueous Na2CO3 (50 mL). The organic layer was dried over MgSO4 and then concentrated. The crude material was purified by ISCO® chromatography using 1-2% EtOAc in hexane to obtain the desired product (2.4 g, 76%). 1H NMR (400 MHz, DMSO-d6) δ 8.02 (s, 1H), 8.0 (d, 1H), 7.51 (d, 1H), 2.79 (s, 3H); LC-MS m/z[M+H]+ 260.3 & 262.2, RT 3.82 min.

Workup

  1. washwashed with saturated, aqueous Na2CO3 (50 mL)
  2. dry with materialThe organic layer was dried over MgSO4
  3. concentrationconcentrated
  4. customThe crude material was purified by ISCO® chromatography

Sources & evidence

ORD record
ord-4a4069f37ac4492fba1b39e70e9aca41
Source dataset
uspto-grants-2013_04
Patent number
US08431695B2

Reaction notes

Loading…