Bromine → Methyl 2-bromo-4-methyl-6-benzothiazolecarboxylate

HRID 1748189Notes

Reaction equation

HRID 1748189 reaction equation
N[C:2]1[S:3][C:4]2[CH:10]=[C:9]([C:11]([O:13][CH3:14])=[O:12])[CH:8]=[C:7]([CH3:15])[C:5]=2[N:6]=1.NC1C=CC(C(OC)=O)=CC=1C.[Br:28]Br>CC(O)=O>[Br:28][C:2]1[S:3][C:4]2[CH:10]=[C:9]([C:11]([O:13][CH3:14])=[O:12])[CH:8]=[C:7]([CH3:15])[C:5]=2[N:6]=1

Participants

5

Reactant 3

HCID 24408BromineHCID 2736799Methyl 4-amino-3-methylbenzoateHCID 22634159HCID 22634159, compound

Product 1

HCID 67984016Methyl 2-bromo-4-methyl-6-benzothiazolecarboxylate

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent2×

Conditions

Temperature
0 °C

Procedure

Methyl 2-amino-4-methyl-benzothiazole-6-carboxylate (I-16A). Into a 500-mL round-bottom flask was placed a solution of methyl 4-amino-3-methylbenzoate (4.00 g, 24.2 mmol, 1.00 equiv) and NaSCN (7.00 g, 86.4 mol, 3.57 equiv) in AcOH (90 mL) that was cooled to 0° C. This was followed by the addition of a solution of Br2 (3.9 g, 25 mmol, 1.0 equiv) in AcOH (25 mL) dropwise, maintaining at 0° C. over 20 min. The resulting solution was allowed to warm to RT on its own accord (over approximately 10 min.) and stirred for 48 hrs at RT. At this time, the solids of the reaction were filtered out. The resulting solution was diluted with 100 mL H2O. The pH value of the solution was adjusted to 8-9 with ammonia (using Whatman PH strip paper to monitor PH adjustment) which furnished an immediate precipitation. The solids were collected by filtration and washed once with ice cold MeOH (50 mL) to afford as a yellow solid. MS m/z 223.0 (M+11). 1H NMR (400 MHz, MeOH-d4) δ 8.17 (app d, J=1.0 Hz, 1H), 8.03 (br s, 2H, NH2), 7.68 (s, 1H), 3.82 (s, 3H), 2.42 (s, 3H).

Workup

  1. customInto a 500-mL round-bottom flask was placed
  2. temperatureto warm to RT on its own accord (over approximately 10 min.)
  3. filtrationAt this time, the solids of the reaction were filtered out
  4. additionThe resulting solution was diluted with 100 mL H2O
  5. customfurnished
  6. customan immediate precipitation
  7. filtrationThe solids were collected by filtration
  8. washwashed once with ice cold MeOH (50 mL)
  9. customto afford as a yellow solid

Sources & evidence

ORD record
ord-c82db3d3e8eb445688fc3fa098515649
Source dataset
uspto-grants-2015_10
Patent number
US09150568B2

Reaction notes

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