Water → HCID 20093923, compound

HRID 273800Notes

Reaction equation

HRID 273800 reaction equation
[Br:1][C:2]1[C:3]2[C:4]3[N:5]([CH2:12][CH2:13][N:14]=3)[CH:6]=[N:7][C:8]=2[CH:9]=[CH:10][CH:11]=1.O>C1C=CC=CC=1.[O-2].[O-2].[Mn+4]>[Br:1][C:2]1[C:3]2[C:4]3[N:5]([CH:12]=[CH:13][N:14]=3)[CH:6]=[N:7][C:8]=2[CH:9]=[CH:10][CH:11]=1

Participants

5

Reactant 2

HCID 962WaterHCID 20094152HCID 20094152, compound

Product 1

HCID 20093923HCID 20093923, compoundYield 53.6%

Reagents, catalysts & solvents 2

HCID 178418406HCID 178418406, compoundCatalystHCID 241BenzeneSolvent

Procedure

4. 242 g of manganese dioxide are added to a warm solution of 22 g of 10-bromo-2,3-dihydroimidazo[1,2-c]quinazoline in 2 l of benzene in a reaction vessel which is provided with a water separator. The mixture is heated at reflux temperature for 15 h. Then, a further 8 g of maganese dioxide are added thereto and the mixture is heated at reflux temperature for a further 1 h. The hot reaction mixture is filtered over Dicalite. The filter cake is rinsed with 1 l of hot benzene, then again boiled up in 1.5 l of dichloromethane/ethanol 199:1 and again filtered. The filtered solutions are concentrated to about 1.51 in a vacuum. A byproduct crystallizes and is filtered off (1.65 g). The filtrate is chromatographed over a column of 2 kg of silica gel. A total of 12.0 g of the desired product is eluted with dichloromethane/ethanol 99:1. 11.7 g of 10-bromoimidazo[1,2-c]quinazoline of m.p. 215°-216° C. are obtained after crystallization from ethyl acetate.

Workup

  1. temperatureThe mixture is heated
  2. temperatureat reflux temperature for 15 h
  3. temperaturethe mixture is heated
  4. temperatureat reflux temperature for a further 1 h
  5. filtrationThe hot reaction mixture is filtered over Dicalite
  6. washThe filter cake is rinsed with 1 l of hot benzene
  7. filtrationagain filtered
  8. concentrationThe filtered solutions are concentrated to about 1.51 in a vacuum
  9. customA byproduct crystallizes
  10. filtrationis filtered off (1.65 g)
  11. customThe filtrate is chromatographed over a column of 2 kg of silica gel
  12. washA total of 12.0 g of the desired product is eluted with dichloromethane/ethanol 99:1

Sources & evidence

ORD record
ord-1fabeda4ec984bf7bb970becf901353a
Source dataset
uspto-grants-1995_02
Patent number
US05387585

Reaction notes

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