title: [3+3] Annulation of donor-acceptor cyclopropanes with mercaptoacetaldehyde: application to the synthesis of tetrasubstituted thiophenes.
abstract: A conceptually new method for synthesis of tetrasubstituted thiophenes in two steps from trans-2-aroyl-3-aryl-cyclopropane-1,1-dicarboxylates and 1,4-dithiane-2,5-diol has been developed. It involves AlCl3-mediated [3+3] annulation of the cyclopropane-derived 1,3-zwitterionic intermediates with in situ generated mercaptoacetaldehyde, followed by DBU-induced rearrangement of the resulting tetrahydrothiopyranols. The target thiophenes are produced in 55-82% yields.
authors.affiliation: School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India. srinivasank@bdu.ac.in.
authors.forename: Gopal
authors.initials: G
authors.lastname: Sathishkannan
authors.forename: Kannupal
authors.initials: K
authors.lastname: Srinivasan
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D003521:Cyclopropanes / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013876:Thiophenes / Q000138:chemical synthesis*
chemical_list: D000447:Aldehydes; D017607:Aluminum Compounds; D002712:Chlorides; D003521:Cyclopropanes; D013438:Sulfhydryl Compounds; D013876:Thiophenes; D000077410:Aluminum Chloride