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Thiophene 3-bromo-, from 2-bromothiophene

Halothiophenes, which are not activated through the presence of —I—M-substituents, undergo substitution smoothly under more forcing conditions with copper salts in pyridine or quinoline. Hence 3-cyanothiophene and 5-methyl-2-cyanothiophene have been obtained from the corresponding bromo compounds. 2-Bromothiophene reacts readily with aliphatic cuprous mercaptides in quinoline at 200°C to give thioethers in high yields. The use of the copper-catalyzed Williamson synthesis of alkoxythiophenes from iodo- or bromo-thiophenes and alcoholate has been mentioned before. The reaction of 2-bromothiophene with acetanilide in nitrobenzene in... [Pg.71]

The preparation of thieno[3,2-fc]thiophene was reported by Iddon and co-workers [76, 77] and it is readily prepared in four steps from commercially available 3-bromothiophene (Scheme 17.1). Thus 3-bromo-thiophene can be lithiated in the 2-position with a bulky non-nucleophilic base such as lithium diisopropylamine. Quenching of the resulting thiophene anion with dimethylfonnamide or tV-formylpiperidine afforded the thiophene aldehyde. Treatment of this o-bromoaldehyde with ethyl 2-sulfanylacetate in the presence of base afforded thieno[3,2-fc]thiophene carboxylate ester in good yield. Hydrolysis of the ester group, followed by thermal decarboxylation of the resulting acid with quinoline in the presence of copper, afforded the unsubstituted thieno[3,2-f>]thiophene in overall yields of approximately 60 % over the four steps. [Pg.662]


See other pages where Thiophene 3-bromo-, from 2-bromothiophene is mentioned: [Pg.183]    [Pg.79]    [Pg.70]    [Pg.79]    [Pg.676]    [Pg.234]    [Pg.133]    [Pg.320]    [Pg.357]    [Pg.79]    [Pg.831]    [Pg.128]    [Pg.462]    [Pg.79]    [Pg.831]    [Pg.461]    [Pg.41]    [Pg.172]    [Pg.176]    [Pg.364]    [Pg.252]    [Pg.87]    [Pg.118]    [Pg.154]    [Pg.96]    [Pg.90]    [Pg.588]    [Pg.318]    [Pg.320]    [Pg.22]    [Pg.385]    [Pg.386]    [Pg.389]    [Pg.136]    [Pg.627]    [Pg.41]    [Pg.288]    [Pg.262]    [Pg.90]    [Pg.51]   
See also in sourсe #XX -- [ Pg.266 ]




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From thiophenes

Thiophen bromo

Thiophene, 3-bromo

Thiophenes 3-bromo

Thiophenes 3-bromo-, from 2-bromothiophene

Thiophenes 3-bromo-, from 2-bromothiophene

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