Pd-Catalyzed Substitution of the OH Group of Nonderivatized Allylic Alcohols by Phenols

Nonactivated phenols have been employed as nucleophiles in the allylation of nonderivatized allylic alcohols to generate allylated phenolic ethers with water as the only byproduct. A Pd­[BiPhePhos] catalyst was found to be reactive to give the O-allylated phenols in good to excellent yields in the presence of molecular sieves. The reactions are chemoselective in which the kinetically favored O-allylated products are formed exclusively over the thermodynamically favored C-allylated products

Equilibrium Study of Pd(dba)₂ and P(OPh)₃ in the Pd-Catalyzed Allylation of Aniline by Allyl Alcohol

Reaction of Pd­(dba)₂ and P­(OPh)₃ shows a unique equilibrium where the Pd­[P­(OPh)₃]₃ complex is favored over both Pd­(dba)­[P­(OPh)₃]₂ and Pd­[P­(OPh)₃]₄ complexes at room temperature. At a lower temperature, Pd­[P­(OPh)₃]₄ becomes the most abundant complex in solution. X-ray studies of Pd­[P­(OPh)₃]₃ and Pd­(dba)­[P­(OPh)₃]₂ complexes show that both complexes have a trigonal geometry with a Pd–P distance of 2.25 Å due to the π-acidity of the phosphite ligand. In solution, pure Pd­(dba)­[P­(OPh)₃]₂ complex equilibrates to the favored Pd­[P­(OPh)₃]₃ complex, which is the most stable complex of those studied, and also forms the most active catalytic species. This catalyst precursor dissociates one ligand to give the reactive Pd­[P­(OPh)₃]₂, which performs an oxidative addition of nonmanipulated allyl alcohol to generate the π-allyl-Pd­[P­(OPh)₃]₂ intermediate according to ESI-MS studies

Equilibrium Study of Pd(dba)₂ and P(OPh)₃ in the Pd-Catalyzed Allylation of Aniline by Allyl Alcohol

Reaction of Pd­(dba)₂ and P­(OPh)₃ shows a unique equilibrium where the Pd­[P­(OPh)₃]₃ complex is favored over both Pd­(dba)­[P­(OPh)₃]₂ and Pd­[P­(OPh)₃]₄ complexes at room temperature. At a lower temperature, Pd­[P­(OPh)₃]₄ becomes the most abundant complex in solution. X-ray studies of Pd­[P­(OPh)₃]₃ and Pd­(dba)­[P­(OPh)₃]₂ complexes show that both complexes have a trigonal geometry with a Pd–P distance of 2.25 Å due to the π-acidity of the phosphite ligand. In solution, pure Pd­(dba)­[P­(OPh)₃]₂ complex equilibrates to the favored Pd­[P­(OPh)₃]₃ complex, which is the most stable complex of those studied, and also forms the most active catalytic species. This catalyst precursor dissociates one ligand to give the reactive Pd­[P­(OPh)₃]₂, which performs an oxidative addition of nonmanipulated allyl alcohol to generate the π-allyl-Pd­[P­(OPh)₃]₂ intermediate according to ESI-MS studies

Green Diesel from Kraft Lignin in Three Steps

Precipitated kraft lignin from black liquor was converted into green diesel in three steps. A mild Ni-catalyzed transfer hydrogenation/hydrogenolysis using 2-propanol generated a lignin residue in which the ethers, carbonyls, and olefins were reduced. An organocatalyzed esterification of the lignin residue with an insitu prepared tall oil fatty acid anhydride gave an esterified lignin residue that was soluble in light gas oil. The esterified lignin residue was coprocessed with light gas oil in a continous hydrotreater to produce a green diesel. This approach will enable the development of new techniques to process commercial lignin in existing oil refinery infrastructures to standardized transportation fuels in the future.RenFuel AB thanks the Swedish Energy Agency for financial support.Löfstedt, J.; Dahlstrand, C.; Orebom, A.; Meuzelaar, G.; Sawadjoon, S.; Galkin, MV.; Agback, P.... (2016). Green Diesel from Kraft Lignin in Three Steps. ChemSusChem. 9(12):1392-1396. doi:10.1002/cssc.201600172S1392139691