title: Palladium(II)-Catalyzed C-H Bond Activation/C-C and C-O Bond Formation Reaction Cascade: Direct Synthesis of Coumestans.
abstract: A palladium catalyzed cascade reaction of 4-hydroxycoumarins and in situ generated arynes has been developed for the direct synthesis of coumestans. This cascade strategy proceeds via C-H bond activation/C-O and C-C bond formations in a single reaction vessel. This methodology affords moderate to good yields of coumestans and is tolerant of a variety of functional groups including halide. The methodology was applied to the synthesis of natural product flemichapparin C.
authors.affiliation: Applied Organic Chemistry Group, Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology , Assam Jorhat 785006, India.
authors.forename: Kashmiri
authors.initials: K
authors.lastname: Neog
authors.affiliation: Applied Organic Chemistry Group, Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology , Assam Jorhat 785006, India.
authors.forename: Ashwini
authors.initials: A
authors.lastname: Borah
authors.affiliation: Applied Organic Chemistry Group, Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology , Assam Jorhat 785006, India.
authors.forename: Pranjal
authors.initials: P
authors.lastname: Gogoi
mesh_terms: D002244:Carbon / Q000737:chemistry*; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002384:Catalysis; D003374:Coumarins / Q000138:chemical synthesis*; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D066244:Proton Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D003374:Coumarins; D010165:Palladium; D002244:Carbon; D006859:Hydrogen; C505898:coumestan