title: Heterobimetallic Pd-Sn catalysis: a Suzuki, tandem ring-closing sequence toward indeno[2,1-b]thiophenes and indeno[2,1-b]indoles.
abstract: Indeno[2,1-b]thiophene and indeno[1,2-b]indole motifs have been obtained in moderate to good yields from easily available substituted boronic acids, 2-bromo aryl/vinyl aldehydes, and nucleophiles such as arenes/heteroarenes and others using a catalytic combination of bimetallic "Pd-Sn" and AgPF(6). This formal three-component coupling involves a Suzuki reaction followed by nucleophile assisted tandem ring closure. The sequential synthesis of substituted heterocycle-fused indenes, benzofluorene, and fluorenes was also accomplished.
authors.affiliation: Organometallics & Catalysis Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
authors.forename: Debjit
authors.initials: D
authors.lastname: Das
authors.forename: Sanjay
authors.initials: S
authors.lastname: Pratihar
authors.forename: Sujit
authors.initials: S
authors.lastname: Roy