A ligand having the structure or its enantiomer; (I) wherein: each one of R.sub.a, R.sub.b, R.sub.c and R.sub.d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH.sub.2NH; *CH(CH.sub.3)NH(C*,R); and the organocatalyst is an organic molecule catalyst covalently bound to the bridge group. Also, a catalyst having the structure or its enantiomer: (II) wherein: each one of R.sub.a, R.sub.b, R.sub.c and R.sub.d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH.sub.2NH; *CH(CH.sub.3)NH(C*,R); and *CH(CH.sub.3)NH(C*,S); the organocatalyst is an organic molecule catalyst covalently bound to the bridge group; and M is selected from the group consisting of Rh, Pd, Cu, Ru, Ir, Ag, Au, Zn, Ni, Co, and Fe. ##STR00001##

A process for preparing a catalyst material, includes: (a) providing a support material having surface hydroxyl (OH) groups, the support material is ceria (CeO.sub.2), zirconia (ZrO.sub.2) or a combination, and the support material contains between 0.3 and 2.0 mmol OH groups/g of the support material; (b) reacting the support material with at least one of: (b1) a compound containing at least one alkoxy or phenoxy group bound though its oxygen atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W); (b2) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element from Group 5 or 6; (b3) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element which is copper (Cu); and (c) calcining the product obtained in step (b).

An organometallic complex catalyst that makes it possible to obtain a higher yield of a desired product than conventional catalysts in a cross-coupling reaction. The organometallic complex catalyst has a structure represented by formula (1) and is for use in a cross-coupling reaction. In formula (1), M is the coordination center and represents a metal atom such as Pd or an ion thereof. R1, R2, and R3 may be the same or different and are a substituent such as a hydrogen atom. R4, R5, R6, and R7 may be the same or different and are a substituent such as a hydrogen atom. X represents a halogen atom. R8 represents a substituent that has a π bond and 3-20 carbon atoms. With regard to the electron-donating properties of R1-R7 with respect to the coordination center M of the ligand containing R1-R7 that is indicated in formula (2), R1-R7 are arranged in combination such that the TEP value obtained from infrared spectroscopy shifts toward the low frequency side compared to the TEP value of the ligand of formula (2-1).

##STR00001##

A catalyst which can catalyze ring-addition reaction of CO.sub.2 and an alkylene oxide at 0˜180° C. under 0.1˜8.0 MPa to produce a corresponding cyclic carbonate, and the preparation thereof. The catalyst is a conjugated microporous macromolecule polymer complexed with cobalt, chromium, zinc, copper or aluminium, and by using the macromolecule catalyst complexed with different metals to catalyze the reaction of CO.sub.2 and alkylene oxide at normal temperature and normal pressure, a yield of the corresponding cyclic carbonate of 35%˜90% can be obtained. The catalyst is easy to recover and the re-use of the catalyst has no influence on the yield; additionally, the yield can reach over 90% by controlling the reaction conditions.

A new metal organic framework (MOF) series and method of synthesizing the same are disclosed which includes an organic linking ligand having the formula: ##STR00001##
and a metal ion bonded to the organic linking ligand.

The present technology provides a foam-forming composition comprising at least one polyol, at least one isocyanate, at least one copper catalyst composition, and at least one surfactant. The copper catalyst composition may comprise a copper (II) compound dissolved in a solvent. In one embodiment, the copper catalyst composition comprises (Cu(II)(acac).sub.2) dissolved in DMSO.

According to some embodiments, the present invention provides compositions and methods for making and using multifunctional polymerized liposomes finding relevant application in medical sciences, particularly in bioimaging, diagnostics, drug delivery, and drug formulation. The compositions and methods involve lipids that are both polymerizable and have a “clickable” group that provides the ability to functionalize via a click reaction with various functional moieties useful for the above-listed applications.

Polyisocyanate-based polymers are formed by curing a reaction mixture containing at least one polyisocyanate and at least one isocyanate-reactive compound having at least two isocyanate-reactive groups in the presence of a copper catalyst that contains at least one copper atom associated with a polydentate ligand that contains at least one nitrogen-containing complexing site.

A catalyst system includes a transition metal salt containing a halo group, an acetate group, or a combination thereof, and an organic phosphine ligand. The molar ratio of the organic phosphine ligand to the transition metal salt is greater than 0 and less than or equal to 50.

The present disclosure provides a low-molecular-weight Tremella aurantialba glucuronoxylomannan (LTAG) as well as a preparation method and an application thereof, and specifically relates to the technical field of medicine. The LTAG provided in the present disclosure has a weight-average molecular weight of 8,000-24,000 Da. In the method of preparing LTAG as provided in the present disclosure, Tremella aurantialba glucuronoxylomannan is depolymerized by peroxides so as to get low-molecular-weight products, which are then exchanged into pharmaceutically acceptable salts through cation exchange resins. The resulting LTAG has a clear structure, a low viscosity and a good solubility, has a strong immune-enhancing activity, and is capable of acting on TLR4 receptor-activated macrophagocytes and promoting the production of various immune factors, so it can be used in the prevention and/or treatment of immunodeficiency-related diseases.