Thionyl Chloride → 4-Oxo-4H-chromene-3-carbonitrile

HRID 2048959

反応式

HRID 2048959 の反応式
O1C2C(=CC=CC=2)C(=O)C(C(O)=O)=C1.S(Cl)(Cl)=O.[O:19]1[C:28]2[C:23](=[CH:24][CH:25]=[CH:26][CH:27]=2)[C:22](=[O:29])[C:21]([C:30]([NH2:32])=O)=[CH:20]1>CN(C)C=O>[C:30]([C:21]1[C:22](=[O:29])[C:23]2[C:28](=[CH:27][CH:26]=[CH:25][CH:24]=2)[O:19][CH:20]=1)#[N:32]

参加物

5

反応物 3

HCID 24386Thionyl Chloride2 回HCID 181620Chromone-3-carboxylic acidHCID 12200777HCID 12200777、化合物2 回

生成物 1

HCID 5212984-Oxo-4H-chromene-3-carbonitrile収率 75%

試薬・触媒・溶媒 1

HCID 6228Dimethylformamide溶媒

実験手順

The present invention concerns a novel method of preparing these 3-cyanochromones from chromone-3-carboxylic acids. The reaction mechanism of the present invention may best be described by the following reaction scheme: ##STR4## Referring to the reaction scheme, chromone-3-carboxylic acid is initially converted to the acyl chloride by treating with thionyl chloride as disclosed in U.S. Pat. No. 3,849,446 to Von Strandtmann, et al., issued Nov. 19, 1974. The acyl chloride is then converted to the corresponding chromone-3-carboxamide, as disclosed in U.S. Pat. No. 3,862,143. The critical feature of the present invention is the further dehydration of the chromone-3-carboxamide with thionyl chloride in N,N-dimethylformamide to give the desired 3-cyanochromone in a high yield of at least 75%. Generally, a molar excess of thionyl chloride and a 30-40 molar excess of N,N-dimethylformamide are employed.

後処理

  1. customThe reaction mechanism of the present invention may best be described by the following reaction scheme

出典と根拠

ORDレコード
ord-4528319ddc564a6fbbcc2626b18674de
出典データセット
uspto-grants-1980_04
特許番号
US04196128

関連ノート

読み込み中…