2-Thiophenecarboxylic acid → 5-Chloromethyl-2-thienylcarboxylic acid

HRID 1604909ノート

反応式

HRID 1604909 の反応式
[S:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[C:6]([OH:8])=[O:7].[Cl:9][CH2:10]OCCl.[Cl-].[Al+3].[Cl-].[Cl-]>C(Cl)(Cl)Cl>[Cl:9][CH2:10][C:5]1[S:1][C:2]([C:6]([OH:8])=[O:7])=[CH:3][CH:4]=1

参加物

5

反応物 3

HCID 107002-Thiophenecarboxylic acidHCID 10967Bis(Chloromethyl) EtherHCID 6451240Aluminum(III) Chloride

生成物 1

HCID 227677545-Chloromethyl-2-thienylcarboxylic acid

試薬・触媒・溶媒 1

HCID 6212Chloroform溶媒

実験手順

2-Thiophenecarboxylic acid is treated in a solution of chloroform with chloromethyl ether in the presence of 0.9 to 2.2 equivalents of aluminum chloride to give 5-chloromethyl-2-thienylcarboxylic acid. Treatment of the obtained acid with excess thionyl chloride at room temperature for about 16 hours yields the acid chloride which is reacted with diazomethane to give the corresponding diazoketone. A methanol solution of the diazoketone is irradiated under nitrogen for about one hour with a high pressure mercury lamp using a Quartz filter. The methyl 5-chloromethyl-2-thienylacetate is obtained upon work up and column chromatography on silica gel. The acetate is hydrolyzed by treatment of a 1:1 mixture of acetic acid and concentrated hydrochloric acid at room temperature overnight to give 5-chloromethyl-2-thienylacetic acid.

出典と根拠

ORDレコード
ord-b9aa38267b634218935c1f251f33e7c2
出典データセット
uspto-grants-1976_04
特許番号
US03948904

反応ノート

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