Sulfuric Acid → 6,7-Dimethoxy-1-oxo-1,2-dihydroisoquinoline-4-carbonitrile

HRID 1822761Notes

Reaction equation

HRID 1822761 reaction equation
S(=O)(=O)(O)O.C([O:8][C:9](=O)[NH:10][CH:11]=[C:12]([C:23]#[N:24])[C:13]1[CH:18]=[CH:17][C:16]([O:19][CH3:20])=[C:15]([O:21][CH3:22])[CH:14]=1)C.C1(OC2C=CC=CC=2)C=CC=CC=1>CCOCC>[CH3:22][O:21][C:15]1[CH:14]=[C:13]2[C:18](=[CH:17][C:16]=1[O:19][CH3:20])[C:9](=[O:8])[NH:10][CH:11]=[C:12]2[C:23]#[N:24]

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 7583Diphenyl EtherHCID 69551232[2-Cyano-2-(3,4-dimethoxy-phenyl)-vinyl]-carbamic acid ethyl ester

Product 1

HCID 220483556,7-Dimethoxy-1-oxo-1,2-dihydroisoquinoline-4-carbonitrileYield 74.3%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Conditions

Temperature
230 °C

Procedure

Concentrated sulfuric acid (0.4 mL) was added the the mixture of [2-cyano-2-(3,4-dimethoxy-phenyl)-vinyl]-carbamic acid ethyl ester (33.5 g, 121 mmol) and diphenyl ether (230 mL). The mixture was heated to 230° C. for 6 hr. After cooling, ether was added to precipitate the solid. The resulting solid was collected by filtration, washed with ether and dried to afford 6,7-dimethoxy-1-oxo-1,2-dihydro-isoquinoline-4-carbonitrile (20.7 g, 74.1%) as a brown solid which was used without further purification. LC-MS m/e calcd for C12H10N2O3 (MH+) 231. found 231.

Workup

  1. temperatureAfter cooling
  2. customto precipitate the solid
  3. filtrationThe resulting solid was collected by filtration
  4. washwashed with ether
  5. customdried

Sources & evidence

ORD record
ord-721d2b6897f74993bef0610a6af25410
Source dataset
uspto-grants-2006_05
Patent number
US07037924B2

Reaction notes

Loading…