title: Selective hydroformylation-hydrogenation tandem reaction of isoprene to 3-methylpentanal.
abstract: The hydroformylation of isoprene catalysed by rhodium phosphine complexes usually yields a broad mixture of the monoaldehydes, the isomeric methylpentenals, as well as the dialdehyde 3-methyl-1,6-hexandial. Under usual reaction conditions the products of a consecutive hydrogenation are only formed as minor by-products. Surprisingly we discovered now a selective auto-tandem reaction consisting of a hydroformylation and a hydrogenation step if a rhodium complex with the chelate ligand bis(diphenylphosphino)ethane is used as catalyst. If branched aromatic solvents like cumene are applied the conversion of isoprene is nearly quantitatively and the yield of the tandem product 3-methylpentanal amounts to 85%.
authors.affiliation: Lehrstuhl für Technische Chemie A, Technische Universität Dortmund, Germany. behr@bci.tu-dortmund.de
authors.forename: Arno
authors.initials: A
authors.lastname: Behr
authors.forename: Sebastian
authors.initials: S
authors.lastname: Reyer
authors.forename: Nils
authors.initials: N
authors.lastname: Tenhumberg
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry*; D002070:Butadienes / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry; D045782:Hemiterpenes / Q000737:chemistry*; D006865:Hydrogenation; D007700:Kinetics; D010420:Pentanes / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry; D012238:Rhodium / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D002070:Butadienes; D056831:Coordination Complexes; D045782:Hemiterpenes; D010420:Pentanes; D010720:Phosphines; C005059:isoprene; D012238:Rhodium; C044646:phosphine