Disclosed are a chiral multidentate ligand (I), a preparation, and an application thereof. In this method, compound (M1) is subjected to condensation with compound (M2) followed by amine deprotection in the presence of a deprotection reagent to obtain compound (M4). Compound (1) is subjected to deprotonation by butyl lithium and phosphorization followed by dimethylamino group substitution to produce compound (3). The compound (3) and the compound (M4) are reacted in the presence of triethylamine to produce chiral multidentate ligands.

##STR00001##

The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

The present disclosure relates to a ferrocene-based compound having high selectivity for sulfide ion. The ferrocene-based compound is obtained by reacting a ferrocene starting material with one or more organic compound selected from a nitrile, a methyl ester and an ethyl ester, and a chemical sensor in solution state is prepared by mixing the compound with an organic solvent. The chemical sensor according to the present disclosure has high selectivity and sensitivity for sulfide ion even at low concentration and may be used as a chemical sensor for detecting hydrogen sulfide in solution state by allowing visual inspection of sulfide ion. In addition, the present disclosure provides a hydrogen sulfide detection kit including an airtight container including an opening/closing door and a detection material inlet, a detection unit which is provided inside the airtight container and composed of paper or fabric to which a ferrocene compound is adsorbed, and a basic reagent which is stored inside or outside the airtight container and generates sulfide ion from hydrogen sulfide. According to the present disclosure, hydrogen sulfide can be detected in real time by generating sulfide ion from hydrogen sulfide in gas or liquid state and visually inspecting the color change of the ferrocene compound of the detection kit.

The present disclosure relates to a ferrocene-based compound having high selectivity for sulfide ion. The ferrocene-based compound is obtained by reacting a ferrocene starting material with one or more organic compound selected from a nitrile, a methyl ester and an ethyl ester, and a chemical sensor in solution state is prepared by mixing the compound with an organic solvent. The chemical sensor according to the present disclosure has high selectivity and sensitivity for sulfide ion even at low concentration and may be used as a chemical sensor for detecting hydrogen sulfide in solution state by allowing visual inspection of sulfide ion. In addition, the present disclosure provides a hydrogen sulfide detection kit including an airtight container including an opening/closing door and a detection material inlet, a detection unit which is provided inside the airtight container and composed of paper or fabric to which a ferrocene compound is adsorbed, and a basic reagent which is stored inside or outside the airtight container and generates sulfide ion from hydrogen sulfide. According to the present disclosure, hydrogen sulfide can be detected in real time by generating sulfide ion from hydrogen sulfide in gas or liquid state and visually inspecting the color change of the ferrocene compound of the detection kit.

The present invention provides novel transition-metal precatalysts that are useful in preparing active coupling catalysts. In certain embodiments, the precatalysts of the invention are air-stable and moisture-stable. The present invention further provides methods of making and using the precatalysts of the invention.

The present invention provides novel transition-metal precatalysts that are useful in preparing active coupling catalysts. In certain embodiments, the precatalysts of the invention are air-stable and moisture-stable. The present invention further provides methods of making and using the precatalysts of the invention.

The present invention relates to biomolecule conjugates which comprise a biomolecule wherein at least one non-natural amino acid (NNAA) is integral to the structure of the biomolecule and wherein the NNAA is a point of attachment of a linker to which a payload, particularly a cytotoxic agent, is attached. More specifically, this invention relates to conjugates of cell-binding agents and active release products comprising cytotoxic agents wherein the conjugates are produced by means of a cycloaddition reaction. Methods of production, pharmaceutical compositions and methods of use are provided.

A series of new macrocycles and cage-like molecules are obtained in a high yield from a bis-(2,4-dialkoxyphenyl)arene (naphthalene, anthracene, pyrene, porphyrin, etc.) or a tris-(2,4-dialkoxyphenyl)arene (benzene, sym-tribenzobenzene) and paraformaldehyde under the catalysis of a Lewis acid. In addition, perhydroxybiphenylarenes (tetrabiphenyl trimer, naphthalene dimer, etc.) can be obtained by means of demethylation, and a variety of water-soluble derivatives can be obtained by further modification, with same exhibiting a good bond ability for guest molecules (purpurine, etc.). Moreover, the functional group introduced into the backbone enables the macrocycle to have excellent adsorption and separation capabilities and a photophysical property. The macrocyclic and cage-like molecules have commercially available raw materials, are simple to synthesize, have a high yield, and are convenient to modify, such that same have wide application prospects in gas adsorption and separation, facilitate performance improvement of luminescent materials, perform adsorption of water-soluble toxic substances, etc.

The present invention is to provide a hydrogen oxidation catalyst that does not contain platinum. Disclosed is a hydrogen oxidation catalyst that is a dinuclear transition metal complex having a chemical structure represented by the following general formula (1) or (2): ##STR00001##
wherein, in the general formulae (1) and (2), M.sup.1 and M.sup.2 are each independently Fe or Ru; Ar.sup.1 and Ar.sup.2 are each independently a cyclopentadienyl group or a pentamethylcyclopentadienyl group; Ar.sup.3 and Ar.sup.4 are each independently a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms; and Ar.sup.5 is a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, and in the general formula (2), R.sup.1 and R.sup.2 are each independently a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms.