Methyl propiolate → Methyl 9-chloro-4,6-dihydro-4-oxo-3-phenylpyrido[2,1-a]isoindole-1-carboxylate

HRID 1885360Notes

Reaction equation

HRID 1885360 reaction equation
[OH-].[Cl:2][C:3]1[CH:11]=[C:10]2[C:6]([CH2:7][N+:8]3[C:15]([OH:16])=[C:14]([C:17]4[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=4)C(=O)N(C)[C:9]=32)=[CH:5][CH:4]=1.[C:25]([O:29][CH3:30])(=[O:28])[C:26]#[CH:27]>C1(C)C=CC=CC=1>[Cl:2][C:3]1[CH:11]=[C:10]2[C:6]([CH2:7][N:8]3[C:15](=[O:16])[C:14]([C:17]4[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=4)=[CH:27][C:26]([C:25]([O:29][CH3:30])=[O:28])=[C:9]32)=[CH:5][CH:4]=1

Participants

4

Reactant 2

HCID 13536Methyl propiolate2×HCID 1784798909-chloro-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-3-phenyl-6H-pyrimido[2,1-a]isoindol-5-ium hydroxide

Product 1

HCID 18957061Methyl 9-chloro-4,6-dihydro-4-oxo-3-phenylpyrido[2,1-a]isoindole-1-carboxylateYield 48.3%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of 333 mg of 9-chloro-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-3-phenyl-6H-pyrimido[2,1-a]isoindol-5-ium hydroxide (internal salt) and 41 ml of toluene was treated with 0.86 g of methyl propiolate and heated to boiling under reflux for about 6.5 days, and 0.86 ml of methyl propiolate was added thereto every 24 hours. The reaction mixture was then cooled in an ice bath and the separated crystals were filtered off under suction. After recrystallization from N,N-dimethylformamide there was obtained 165 mg of methyl 9-chloro-4,6-dihydro-4-oxo-3-phenylpyrido[2,1-a]isoindole-1-carboxylate as yellowish crystals with a m.p. of 269°-273°.

Workup

  1. temperatureheated
  2. temperatureunder reflux for about 6.5 days
  3. customevery 24 hours
  4. temperatureThe reaction mixture was then cooled in an ice bath
  5. filtrationthe separated crystals were filtered off under suction
  6. customAfter recrystallization from N,N-dimethylformamide

Sources & evidence

ORD record
ord-826fe07c30c94623ae35864ab6910ba0
Source dataset
uspto-grants-1992_09
Patent number
US05143912

Reaction notes

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