A catalyst system includes a complex having formula I which advantageously has a sterically protecting N-heterocyclic carbene (NHC) carbene-pyridine ligand to handle harsh reactions conditions than many prior art catalysts:

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wherein M is a transition metal; o is 0, 1, 2, 3, or 4; R.sub.1 is a C.sub.1-6 alkyl, a C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl. In a refinement, R.sub.1 is methyl, ethyl, butyl, n-propyl, isopropyl, n-butyl, sec-butyl, or t-butyl; R.sub.2, R.sub.3, R.sub.3′ are independently an optionally substituted C.sub.1-6 alkyl, halo (e.g., Cl, F, Br, etc), NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; R.sub.4, R.sub.4′ are independently an optionally substituted C.sub.1-6 alkyl, halo, NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; and X.sup.− is a negatively charge counter ion and L.sub.1, L.sub.2 are each independently a neutral ligand.

The subject invention provides synthetic compounds, and compound complexes having catalytic activities towards oxidation or oxygenation, and/or dehydrogenation of various substrates comprising C—H bonds. The catalysts of the subject invention comprise a dinuclear Cu(I)/Cu(II) center that can convert between a resting state and a reactive species. The subject invention also provides methods of using such catalysts for the oxidation of substrates comprising C—H bonds, e.g., hydrocarbons, to synthesize chemicals for use as pharmaceuticals and industrial feedstock.

Disclosed is a cost-effective process for catalytic conversion of simple C.sub.6-based sugars (such as glucose and fructose) and industrial-grade sugar syrups derived from starch (such as different grades of High Fructose Corn Syrup) and cellulosic biomass to 5-HydroxyMethylFurfural (5-HMF) in a continuous-flow tubular reactor in bi-phasic media using inexpensive heterogeneous solid catalysts. Commercial and synthesized heterogeneous solid catalysts were used and their activities in terms of sugar conversion and HMF selectivity and yield were compared. Continuous dehydration of fructose, glucose and industrial-grade sugar syrups derived from corn and wood to HMF was achieved and the stability of selected catalysts and feasibility of catalyst recycling and regeneration were demonstrated. The performance of the catalysts and reactor system were examined under different operating conditions including reaction temperature, feeding flow rate, initial feedstock concentration, catalyst loading, presence of extracting organic solvent and phase transfer catalyst and aqueous to organic phase ratio. At the best operating conditions, HMF yield attained 60%, 45% and 53%, from dehydration of fructose, glucose and HFCS-90, respectively.

The present invention discloses a method for preparing aldehydes or ketones via aerobic oxidation of alcohols with the copper salts and nitroxide radicals as catalysts. Both oxygen and air could be used as oxidants, after 4 to 48 hours of reaction in an organic solvent at room temperature, the alcohols are efficiently oxidized to the corresponding aldehydes or ketones. The present invention has the following advantages: easy to operate, refraining from using chlorides which are corrosive to equipment, readily available raw materials and reagents, mils reaction conditions, the broad substrate scope, good functional group tolerance, convenient purification, environmentally friendly and no pollution. Thus, the method is suitable for industrial production.

The present application discloses complexes useful as catalysts for organic chemical synthesis including hydrogenation and dehydrogenation of unsaturated compounds or dehydrogenation of substrates. The range of hydrogenation substrate compounds includes esters, lactones, oils and fats, resulting in alcohols, diols, and triols as reaction products. The catalysts of current application can be used to catalyze a hydrogenation reaction under solvent free conditions. The present catalysts also allow the hydrogenation to proceed without added base, and it can be used in place of the conventional reduction methods employing hydrides of the main-group elements. Furthermore, the catalysts of the present application can catalyze a dehydrogenation reaction under homogenous and/or acceptorless conditions. As such, the catalysts provided herein can be useful in substantially reducing cost and improving the environmental profile of manufacturing processes for variety of chemicals.

The subject invention provides synthetic compounds, and compound complexes having catalytic activities towards oxidation or oxygenation, and/or dehydrogenation of various substrates comprising C—H bonds. The catalysts of the subject invention comprise a dinuclear Cu(I)/Cu(II) center that can convert between a resting state and a reactive species. The subject invention also provides methods of using such catalysts for the oxidation of substrates comprising C—H bonds, e.g., hydrocarbons, to synthesize chemicals for use as pharmaceuticals and industrial feedstock.

This invention provides a reversible hydrogen loading and discharging system and a reversible method for loading and discharging hydrogen. The system and the methods of this invention comprise ethylene glycol as a liquid organic hydrogen carrier and at least one transition metal. By reacting ethylene glycol with at least one transition metal; at least one hydrogen molecule and at least one oligoester of ethylene glycol are formed (hydrogen releasing)⋅, and by reacting at least one oligoester of ethylene glycol with at least one transition metal and at least one hydrogen molecule, at least one ethylene glycol is formed (hydrogen loading).

The subject invention provides synthetic compounds, and compound complexes having catalytic activities towards oxidation or oxygenation, and/or dehydrogenation of various substrates comprising C−H bonds. The catalysts of the subject invention comprise a dinuclear Cu(I)/Cu(II) center that can convert between a resting state and a reactive species. The subject invention also provides methods of using such catalysts for the oxidation of substrates comprising C−H bonds, e.g., hydrocarbons, to synthesize chemicals for use as pharmaceuticals and industrial feedstock.

A new heterogeneous catalyst for various organic oxidation processes and a method of making the same by a successful immobilization of a copper (II) bis-Schiff base hydrazone complex on the surface of a composite ZnO—TiO.sub.2 to afford as active catalyst CuL.sub.2Cl.sub.2@ZnO—TiO.sub.2. This novel catalyst can be used to selectively oxidize benzyl alcohol to benzaldehyde.

Various embodiments disclosed relate to bridged phthalocyanine- and napththalocyanine-metal complex catalysts and methods using the same for oxidation reactions. In various embodiments, the present invention provides a method of oxidation including contacting an oxidizable starting material including an alkene with a catalyst and an oxidant, to provide an oxidized product.