3-Phenylnaphtho[2,3-d][1,2]oxazole-4,9-dione → HCID 178510514, compound

HRID 1580618Notes

Reaction equation

HRID 1580618 reaction equation
[C:1]1([C:7]2[C:11]3[C:12](=[O:21])[C:13]4[CH:14]=[CH:15][CH:16]=[CH:17][C:18]=4[C:19](=[O:20])[C:10]=3[O:9][N:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1>CO>[C:7]([C:11]1[C:12](=[O:21])[C:13]2[C:18]([C:19](=[O:20])[C:10]=1[OH:9])=[CH:17][CH:16]=[CH:15][CH:14]=2)(=[NH:8])[C:1]1[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

3

Reactant 1

HCID 151852683-Phenylnaphtho[2,3-d][1,2]oxazole-4,9-dione

Product 1

HCID 178510514HCID 178510514, compoundYield 62.5%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of 3-phenyl-4,9-dihydronaphtho-[2,3-d]isoxazole-4,9-dione (m.p. 133°-135°C, 500 mg) in methanol (400 ml) is irradiated by light of a low-pressure mercury lamp (35 W) at room temperature (20°-30°C) for 3 hours in argon atmosphere. After removal of methanol, the residue is extracted with chloroform. The extract is chromatographed on alumina. The chloroform insoluble residue is dissolved in a mixture of chloroform and methanol, and this solution is also chromatograped on alumina. The fractions containing the objective compound are combined, evaporated, and the residue is recrystallized from 70 % acetic acid to give 2-benzimidoyl-3-hydroxy-1,4-naphthoquinone (315 mg) as pale yellow scales, m.p. 258°14 259°C.

Workup

  1. customAfter removal of methanol
  2. extractionthe residue is extracted with chloroform
  3. customThe extract is chromatographed on alumina
  4. dissolutionThe chloroform insoluble residue is dissolved in a mixture of chloroform and methanol
  5. additionThe fractions containing the objective compound
  6. customevaporated
  7. customthe residue is recrystallized from 70 % acetic acid

Sources & evidence

ORD record
ord-2c0a6f4c8fa44ead9b76a784ab638212
Source dataset
uspto-grants-1976_01
Patent number
US03933828

Reaction notes

Loading…