Methylamine → 6-Ethoxy-2-benzothiazolesulfenamide

HRID 1110374Notes

Reaction equation

HRID 1110374 reaction equation
C[NH2:2].[CH2:3]([O:5][C:6]1[CH:15]=[CH:14][C:9]2[N:10]=[C:11]([SH:13])[S:12][C:8]=2[CH:7]=1)[CH3:4]>[OH-].[Na+]>[CH2:3]([O:5][C:6]1[CH:15]=[CH:14][C:9]2[N:10]=[C:11]([SH:13])[S:12][C:8]=2[CH:7]=1)[CH3:4].[CH2:3]([O:5][C:6]1[CH:15]=[CH:14][C:9]2[N:10]=[C:11]([S:13][NH2:2])[S:12][C:8]=2[CH:7]=1)[CH3:4]

Participants

5

Reactant 2

HCID 6329Methylamine2×HCID 178466040HCID 178466040, compound

Product 2

HCID 136015166-Ethoxy-2-benzothiazolesulfenamideHCID 178466040HCID 178466040, compound

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent

Conditions

Temperature
-10 °C

Procedure

A solution of 40% aqueous methylamine (80 ml) was placed in a 250 ml 3-necked flask, equipped with a powerful stirrer and two-addition funnels. The solution was cooled to -10° C. with an ice/methanol bath. A solution of 6-ethoxy-2-mercaptobenzothiazole (2.0 g., 0.0095 mol) in 20 ml of 5% NaOH was prepared, cooled to 10° C. and placed into one of the addition flasks. The second addition flask was charged with 40 ml of 5.25% NaOC1 which was cooled to 5° C. The two solutions were added simultaneously to the aqueous methylamine over a period of one hour with the rate of addition of the 6-ethoxy-2-mercaptobenzothiazole solution slightly faster than the addition of the NaOC1 solution The temperature of the reaction was maintained at --5° C.-0° C. The reaction was stirred for 15 minutes upon completing the addition and vacuum filtered to yield 6-ethoxy-2-benzothiazolesulfenamide. The 6-ethoxy-2-benzothiazolesulfenamide was immediately dissolved in 100 ml of acetone and oxidized with 50 ml of 5% KMnO4. The temperature of the oxidation was kept below 30° C. The MnO2 was removed by vacuum filtration and the filter cake washed with 25 ml of 5% NaOH. The 6-ethoxy-N-methyl-2-benzothiazolesulfonamide was precipitated from the solution by acidification with 5% HC1 to yield 1.3g. (yield 50.3%). The product was purified by dissolving it in 10% Na2CO3 and precipitating it with 5% Hl. m.p. 129° C.-131° C.; NMR(DMSO- d6) 8.4(s, lH), 8.3-7.1cm, 3H) 4-1 4-3.9(q,1 2H) 2.7(s, 3H 1.5-1.2(t, 3H. IR(KBr) 3100 cm (N-H) 1345 cm-1, 1155 cm (S=O). Elemental Analyses: C10H12N2O3S2 ; Calculated: C 44.09% H 4.44% N 10.28%. Found: C 44.04% H 4.51% N 10.18%.

Workup

  1. customequipped with a powerful stirrer and two-addition funnels
  2. temperaturecooled to 10° C.
  3. additionThe second addition flask was charged with 40 ml of 5.25% NaOC1 which
  4. temperaturewas cooled to 5° C
  5. temperaturewas maintained at --5° C.-0° C
  6. additionthe addition and vacuum
  7. filtrationfiltered

Sources & evidence

ORD record
ord-231d191f458a4f58a2364bf7f06598a9
Source dataset
uspto-grants-1990_12
Patent number
US04975449

Reaction notes

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