3.5- Disubstituted 2-amino-thiophenes

Alkylthio-5-alkylthiophens are chloromethylated at position 3 by chloromethyl methyl ether. 3-Methylthiothiophen has been nitrated at position 2. The influence of the reaction conditions on the isomer distribution in the acylation of 2-methoxy-, 2-methylthio-, and 2-dimethyl-amino-thiophen has been studied. Azo-coupling and aminomethylation occur at position 3 of some 4,5-disubstituted 2-acylaminothiophens. 3-Acetylamino-2-benzoylthiophen yields the 4,5-dichloro-derivative with sulphuryl chloride, while 3-acetylamino- or 3-benzoylamino-4-carbonyl-thiophen derivatives are chlorinated at position 2. ... 

Several thieno[3,2-e]indoles 26 have been obtained by heteroannulation of 5-amino-4-iodobenzo[i ]thiophene with internal alkynes (2009T8497). The synthesis of 7,8-disubstituted thienoindoles was attempted using Pd(OAc)2 with different bases (K2CO3, KOAc, Na2C03, NaOAc) with or without... 

Syntheses of Thiophens by Ring-closure Reactions.—The base-catalysed reaction between 3-amino-substituted dithioacrylate esters or amides (1), which are easily available from trithione, and a-halogenocarbonyl compounds yields 2,5-disubstituted thiophens (2). The same is true for... 

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