Catalysts for hydrodesulfurization

摘要

Phosphoranimide-metal catalysts and their role in hydrodesulfurization and hydrogenation are disclosed. The catalysts comprise of first row transition metals such as nickel, cobalt and iron. The catalysts have a metal to anionic phosphoranimide ratio of 1:1 and have no inactive bulk phase and no dative ancillary ligands. In one embodiment, the catalysts comprise discrete mixed-valent precatalyst clusters, the electronic state of which can be adjusted to optimize catalytic activity. The catalysts catalyze the hydrodesulfurization of a range of sulfur-containing organic compounds under lower temperature and pressure conditions than those conditions commonly used in industrial hydrodesulfurization. The catalysts also catalyze the hydrogenation of substrates comprising at least one carbon-carbon double bond which is not present in an aromatic moiety, although the substrate itself may include an aromatic moiety.

主权项

1. A method of catalyzing a hydrodesulfurization reaction comprising:
reacting an organic substrate having at least one carbon-sulfur bond in the presence of a reducing agent with a catalyst of general formula:
{[A-M(NPR3)]n}m+(Yd−)e  Formula Iwhere:
A is a monoanionic σ-bonded ligand capable of undergoing hydrogenolysis in the presence of hydrogen or hydrosilane; M is Fe, Ni or Co; n equals 2, 3, or 4; m equals 0, 1, 2, 3, or 4; Y is a weakly-coordinating or non-coordinating counter-ion, of formal negative charge ‘d’, and with stoichiometry ‘e’ such that d·e=m, and NPR3 is an anionic phosphoranimide ligand of structure: where: R1, R2, R3 can be the same group or different groups selected from: C1-18 primary, secondary, or tertiary alkyl, a C3-8 cycloalkyl, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or an inert functional group containing at least one heteroatom selected from the group consisting of a Group 15 element, a Group 16 element, silicon, and combinations thereof; wherein R1, R2, R3 may also be linked to give cyclic systems; and wherein the ratio of M to NPR3− in the catalyst is 1:1.