Methyl 2-chloro-4-methylbenzo[d]thiazole-5-carboxylate → 5-Benzothiazolecarboxylic acid,2,3-dihydro-4-methyl-2-oxo-,methyl ester

HRID 1071906ノート

反応式

HRID 1071906 の反応式
Cl[C:2]1[S:3][C:4]2[CH:10]=[CH:9][C:8]([C:11]([O:13][CH3:14])=[O:12])=[C:7]([CH3:15])[C:5]=2[N:6]=1.C[O-:17].[K+]>CN1CCCC1=O>[CH3:15][C:7]1[C:5]2[NH:6][C:2](=[O:17])[S:3][C:4]=2[CH:10]=[CH:9][C:8]=1[C:11]([O:13][CH3:14])=[O:12]

参加物

4

反応物 2

HCID 22390080Methyl 2-chloro-4-methylbenzo[d]thiazole-5-carboxylateHCID 23664618Potassium methoxide

生成物 1

HCID 223900755-Benzothiazolecarboxylic acid,2,3-dihydro-4-methyl-2-oxo-,methyl ester収率 55%

試薬・触媒・溶媒 1

HCID 13387N-methyl-2-pyrrolidone溶媒

反応条件

温度
100 °C

実験手順

A solution of 22.5 g (93 mmol) of methyl 2-chloro-4-methyl-benzothiazole-5-carboxylate in 360 ml of N-methylpyrrolidone was admixed with 13.6 g (186 mmol) of potassium methoxide and heated at 100° C. for 5 hours. After cooling, the resulting precipitate was filtered off with suction and the filtrate was admixed with water. The pH of the reaction solution was then adjusted to pH 1, the aqueous solution was extracted three times with ethyl acetate and the combined organic phases were washed and dried. The solvent was removed under reduced pressure and the residue was purified by trituration with methylene chloride/n-hexane. This gave, in a yield of 55%, 11.38 g (51 mmol) of methyl 4-methylbenzothiazol-2-one-5-carboxylate of m.p. 262° C.-266° C.

後処理

  1. temperatureAfter cooling
  2. filtrationthe resulting precipitate was filtered off with suction
  3. extractionthe aqueous solution was extracted three times with ethyl acetate
  4. washthe combined organic phases were washed
  5. customdried
  6. customThe solvent was removed under reduced pressure
  7. customthe residue was purified by trituration with methylene chloride/n-hexane

出典と根拠

ORDレコード
ord-7b28043bae3a4d7f827f761c5a82f3ac
出典データセット
uspto-grants-2005_06
特許番号
US06908884B2

反応ノート

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