Ethyl propiolate → 5,6-Dihydro-5-oxopyrazolo[1,5-c]quinazoline-2-carboxylic acid ethyl ester

HRID 65683Notes

Reaction equation

HRID 65683 reaction equation
[N+:1](=[C:3]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[NH:5][C:4]1=[O:12])=[N-:2].[C:13]([O:17][CH2:18][CH3:19])(=[O:16])[C:14]#[CH:15]>C1C=CC=CC=1>[O:12]=[C:4]1[N:1]2[N:2]=[C:14]([C:13]([O:17][CH2:18][CH3:19])=[O:16])[CH:15]=[C:3]2[C:11]2[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=2[NH:5]1

Participants

4

Reactant 2

HCID 12182Ethyl propiolateHCID 136455454(3Z)-3-diazo-1H-indol-2-one

Product 1

HCID 1360233445,6-Dihydro-5-oxopyrazolo[1,5-c]quinazoline-2-carboxylic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A solution of 48 g (0.30 mole) of 3-diazooxindole and 38.7 g (0.39 mol) of ethyl propiolate in 2 l. of benzene is refluxed overnight. The reaction mixture is cooled to room temperature and the crude product filtered, wt.=60 g. Crystallization from absolute ethanol gives 54 g, m.p. 242°-244° (Sl. d.).

Workup

  1. filtrationthe crude product filtered
  2. customCrystallization from absolute ethanol
  3. customgives 54 g, m.p. 242°-244° (Sl. d.)

Sources & evidence

ORD record
ord-3d803840950b476982579113b263d705
Source dataset
uspto-grants-1978_12
Patent number
US04128644

Reaction notes

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