Ethyl Acetoacetate → 7-Ethoxy-2,6-dimethylpyrido[1,2-a]pyrimidin-4-one

HRID 128614

反応式

HRID 128614 の反応式
[CH2:1]([O:3][C:4]1[CH:5]=[CH:6][C:7]([NH2:11])=[N:8][C:9]=1[CH3:10])[CH3:2].[C:12](OCC)(=[O:17])[CH2:13][C:14]([CH3:16])=O.[OH-].[Na+]>>[CH2:1]([O:3][C:4]1[CH:5]=[CH:6][C:7]2[N:8]([C:9]=1[CH3:10])[C:12](=[O:17])[CH:13]=[C:14]([CH3:16])[N:11]=2)[CH3:2]

参加物

4

反応物 3

HCID 8868Ethyl AcetoacetateHCID 14798Sodium HydroxideHCID 128750175-Ethoxy-6-methylpyridin-2-amine

生成物 1

HCID 193743257-Ethoxy-2,6-dimethylpyrido[1,2-a]pyrimidin-4-one

反応条件

温度
95 °C

実験手順

A mixture of 5-ethoxy-6-methyl-pyridin-2-amine (22.0 g) and ethyl acetoacetate (22.4 ml) was stirred at ambient temperature while polyphosphoric acid (47 ml) was added slowly. After the addition the mixture was warmed gradually on a steam bath, with caution, until an exotherm occurred with considerable frothing. After the reaction had subsided the mixture was heated for 75 minutes at 95° C., then cooled and added to ice/water. When all the polyphosphoric acid had dissolved the mixture was basified with 5M sodium hydroxide solution and the mixture extracted with dichloromethane to give 7-ethoxy-2,6-dimethylpyrido[1,2-a]pyrimidin-4-one m.p. 112°-114° C. The pyrimidine (12.3 g) was added to stirred paraffin oil (190 ml) at 340° C. over 10 minutes. The mixture was heated at 340° C. for a further 40 minutes then cooled to ambient temperature and diluted with petroleum ether, b.p. 60°-80° C. (180 ml). The mixture was filtered and the solid obtained was washed with ether. The solid was recrystallised from IMS to give 6-ethoxy-2,7-dimethyl-1,8-naphthyridin-4-ol, m.p. 281°-4° C.

後処理

  1. additionwas added slowly
  2. additionAfter the addition the mixture
  3. temperaturewas warmed gradually on a steam bath, with caution, until an exotherm
  4. temperaturecooled
  5. extractionthe mixture extracted with dichloromethane

出典と根拠

ORDレコード
ord-8dc4042b945544af9b2f0ff8cfdc62ba
出典データセット
uspto-grants-1995_11
特許番号
US05464781

関連ノート

読み込み中…