We disclose a nickel/Brønsted acid-catalyzed tandem process consisting of double bond isomerization of allyl ethers and amines and subsequent intramolecular reaction with nucleophiles. The process is accomplished by [(Me 3 P) 4 NiH]N(SO 2 CF 3 ) 2 in the presence of triflic acid. The methodology provides rapid access to tetrahydropyran-fused indoles and other oxacyclic scaffolds under very low catalyst loadings.

We report a catalytic system for direct deoxygenation of benzylic alcohols by using non-precious precatalyst Cp2TiCl2 and 2 MeTHF as solvent. Mechanistic studies showed that the used silane Me(EtO)2SiH acts...

We report a catalytic system for direct deoxygenation of benzylic alcohols by using non-precious precatalyst Cp2TiCl2 and 2 MeTHF as solvent. Mechanistic studies showed that the used silane Me(EtO)2SiH acts both as H-donor and regenerating agent of the active catalytic species. This method tolerates a wide variety of functional and protecting groups and enables sequential deoxygenation-dehalogenation and deoxygenation-hydrogenation reactions. The procedure was successfully applied in the exhaustive reduction of lignin model substrates into value-added compounds.