2-Aminophenol → 2-(2H-Pyrrol-2-ylidene)-2,3-dihydro-1,3-benzoxazole

HRID 6429

반응식

HRID 6429 반응식
[NH:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[C:6]([OH:8])=O.[NH2:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=1O.B(O)(O)O>C1(C)C(C)=CC=CC=1.C(OCC)(=O)C>[NH:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[C:6]1[O:8][C:11]2[CH:12]=[CH:13][CH:14]=[CH:15][C:10]=2[N:9]=1

참가 물질

6

반응물 3

HCID 58012-AminophenolHCID 7628Boric AcidHCID 12473Pyrrole-2-Carboxylic Acid

생성물 1

HCID 1356254822-(2H-Pyrrol-2-ylidene)-2,3-dihydro-1,3-benzoxazole수율 52%

시약·촉매·용매 2

HCID 7237O-Xylene용매HCID 8857Ethyl Acetate용매

실험 절차

2-(Pyrrol-2-yl)benzoxazole was prepared as follows: A mixture of 5.55 g (0.05 mol) of pyrrole-2-carboxylic acid and 5.46 g (0.05 mol) of o-aminophenol and 3.09 g (0.05 mol) boric acid in 50 mL of xylene was heated under reflux for 3 days while removing water which was generated from reaction using a Dean-Stark trap. The cooled reaction mixture was diluted with 100 mL of ethyl acetate, washed with 150 mL of 5% sodium hydroxide solution and then with 150 mL of water. The separated organic layer was dried over anhydrous sodium sulfate. The resulting crude product was purified by column chromatography on silica gel with 20% hexane in chloroform as eluant. The desired product, 2-(pyrrol-2-yl)benzoxazole (4.75 g, 52%), was obtained as a white solid. m.p. 149°-150° C.; 1H NMR (CDCl3) δ6.38-6.40 (m, 1H, ArH), 7.05-7.06 (m, 1H, ArH), 7.11-7.13 (m, 1H, ArH), 7.29-7.36 (m, 2H, 2xArH), 7.53-7.56 (m, 1H, ArH), 7.65-7.69 (m, 1H, ArH), 10.9 (bs, 1H, NH).

후처리

  1. custom2-(Pyrrol-2-yl)benzoxazole was prepared
  2. temperaturewas heated
  3. temperatureunder reflux for 3 days
  4. customwhile removing water which
  5. customwas generated from reaction
  6. customThe cooled reaction mixture
  7. washwashed with 150 mL of 5% sodium hydroxide solution
  8. dry with materialThe separated organic layer was dried over anhydrous sodium sulfate
  9. customThe resulting crude product was purified by column chromatography on silica gel with 20% hexane in chloroform as eluant

출처 및 근거

ORD 기록
ord-2288569fc3ee4fffb9e3876b2052db84
출처 데이터셋
uspto-grants-1993_09
특허 번호
US05248782

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