title: Efficient one-pot synthesis of highly substituted thiophene library from 1,3-dicarbonyl compounds.
abstract: A facile and efficient one-pot synthesis of highly substituted thiophenes has been developed and employed for the preparation of a small focused library. Treatment of 1,3-dicarbonyl compounds 1 with CS2 in the presence of K2CO3 in DMF at room temperature, followed by stepwise addition of alkyl bromides 2 and methylene active bromides 3, provided via intramolecular cyclization 2,3,4,5-tetrasubstituted thiophenes 4 in yields of 77-94%. This protocol, combining construction and modification of the thiophene ring, increases the structural diversity of final products from readily available materials. A mechanism for the one-pot synthesis of thiophenes of type 4 has been proposed. A small focused library of thiophenes is prepared using the sequential addition of reagents to achieve unique substitution in the 2 and 5 position of the thiophene ring.
authors.affiliation: Department of Chemistry, Northeast Normal University, Changchun 130024, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Huang
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Chai
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
authors.forename: Yongjiu
authors.initials: Y
authors.lastname: Liang
authors.forename: Dewen
authors.initials: D
authors.lastname: Dong
mesh_terms: D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D015394:Molecular Structure; D013876:Thiophenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D013876:Thiophenes