Hydrochloric Acid → Methyl 2-thioxo-2,3-dihydrobenzoxazole-4-carboxylate

HRID 249823ノート

反応式

HRID 249823 の反応式
[NH2:1][C:2]1[C:11]([OH:12])=[CH:10][CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].C(O[C:16]([S-])=[S:17])C.[K+].Cl>N1C=CC=CC=1>[S:17]=[C:16]1[NH:1][C:2]2=[C:3]([C:4]([O:6][CH3:7])=[O:5])[CH:8]=[CH:9][CH:10]=[C:11]2[O:12]1

参加物

5

反応物 3

HCID 313Hydrochloric AcidHCID 205248Anthranilic acid, 3-hydroxy-, methyl esterHCID 2735045Potassium ethylxanthate

生成物 1

HCID 22272869Methyl 2-thioxo-2,3-dihydrobenzoxazole-4-carboxylate収率 74.3%

試薬・触媒・溶媒 1

HCID 1049Pyridine溶媒

実験手順

A mixture of methyl 2-amino-3-hydroxybenzoate from Step A (2.04 g, 12.2 mmol) and potassium O-ethylxanthate (1.37 g, 8.56 mmol) in pyridine (8 mL) was heated to reflux for 2 h, then cooled to room temperature and poured into a mixture of ice-water (45 mL) and conc. HCl (4.8 mL). The resulting precipitate was collected by filtration and washed with water, dried on vacuum to give methyl 2-thioxo-2,3-dihydrobenzoxazole-4-carboxylate (1.33 g, 52%) as a light brown solid: 1H NMR (500 MHz, CDCl3) δ 10.40 (br s, 1H), 7.82 (dd, J 8.0, 1.0 Hz, 1H), 7.49 (dd, J 8.0, 1.0 Hz, 1H), 7.28 (t, J=8.0 Hz, 1H), 4.01 (s, 3H); MS (ESI+) m/z 210 (M+H).

後処理

  1. temperaturewas heated
  2. temperatureto reflux for 2 h
  3. filtrationThe resulting precipitate was collected by filtration
  4. washwashed with water
  5. customdried on vacuum

出典と根拠

ORDレコード
ord-bd8e721cb7564a36bd69681269493389
出典データセット
uspto-grants-2011_01
特許番号
US07863271B2

反応ノート

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