Ammonium Hydroxide → 6,7-Dimethoxy-4-ethyl-2(1H)quinazolinone

HRID 1249382Notes

Reaction equation

HRID 1249382 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([NH:11][C:12]([NH:14][C:15](=O)[CH2:16][CH3:17])=[O:13])[CH:6]=[CH:7][C:8]=1[O:9][CH3:10].[NH4+].[OH-]>>[CH3:10][O:9][C:8]1[CH:7]=[C:6]2[C:5](=[CH:4][C:3]=1[O:2][CH3:1])[NH:11][C:12](=[O:13])[N:14]=[C:15]2[CH2:16][CH3:17]

Participants

3

Reactant 2

HCID 14923Ammonium HydroxideHCID 13365109N-(3,4-Dimethoxyphenyl)-N'-propionylurea

Product 1

HCID 1784377956,7-Dimethoxy-4-ethyl-2(1H)quinazolinoneYield 24.6%

Procedure

A suspension of N-(3,4-dimethoxyphenyl)-N'-propionylurea (32.45 g, 128 mM) in polyphosphoric acid (375.12 g, 1109 mM) is heated at 130°-135° C. under nitrogen with vigorous stirring for 3.5 hours. The mixture is then poured onto 500 g ice-H2O and stirred. The solution is brought to pH 5.5 with concentrated NH4OH and allowed to stand at room temperature overnight. A brown precipitate forms. The resulting solid is filtered and dried to yield 7.40 g of a white solid. This filtrate is extracted with CHCl3 (5×250 ml), the organic extract is dried (MgSO4) and the solvent removed in vacuo to give a tan solid. The solid is triturated with acetone and filtered to give a tan solid (4.98 g). A sample is slurried in water and redried for additional purification, m.p. 263°-265° C. δTMSTFA 7.50 (s, 1H, 5--H), 7.23 (s, 1H, 8--H), 4.30 (s, 3H, 6 or 7-OCH3) 4.17 (s, 3H, 6 or 7--OCH3), 3.50 (q, 2H, J=8.0 Hz, CH2CH3), 1.70 (t, 3H, J=8.0 Hz, CH2CH3).

Workup

  1. temperatureis heated at 130°-135° C. under nitrogen
  2. stirringstirred
  3. waitto stand at room temperature overnight
  4. filtrationThe resulting solid is filtered
  5. customdried

Sources & evidence

ORD record
ord-9e1faac1019346ec9e908b17becb669a
Source dataset
uspto-grants-1986_12
Patent number
US04631283

Reaction notes

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