The present invention provides novel cyclic phosphorus-containing compounds, namely hydroxyl-functional phospholene-1-oxides, serving as highly efficient reactive flame retardants in urethane systems, particularly in flexible polyurethane foams, semi-rigid and rigid polyurethane and polyisocyanurate foams. The invention further provides fire-retarded polyurethane compositions comprising said hydroxyl-functional phospholene-1-oxides.

The present invention provides novel cyclic phosphorus-containing compounds, namely hydroxyl-functional phospholene-1-oxides, serving as highly efficient reactive flame retardants in urethane systems, particularly in flexible polyurethane foams, semi-rigid and rigid polyurethane and polyisocyanurate foams. The invention further provides fire-retarded polyurethane compositions comprising said hydroxyl-functional phospholene-1-oxides.

The present invention provides novel cyclic phosphorus-containing compounds, namely hydroxyl-functional phospholene-1-oxides, serving as highly efficient reactive flame retardants in urethane systems, particularly in flexible polyurethane foams, rigid polyurethane foams and rigid polyisocyanurate foams. The invention further provides fire-retarded polyurethane compositions comprising said hydroxyl-functional phospholene-1-oxides.

The present invention provides novel cyclic phosphorus-containing compounds, namely hydroxyl-functional phospholene-1-oxides, serving as highly efficient reactive flame retardants in urethane systems, particularly in flexible polyurethane foams, rigid polyurethane foams and rigid polyisocyanurate foams. The invention further provides fire-retarded polyurethane compositions comprising said hydroxyl-functional phospholene-1-oxides.

An organic compound has a structure as shown in Formula (I). The compound has a phosphorus-oxygen five-membered ring combined with a five-membered ring as an electron acceptor unit. The compound has a high luminous efficiency and a lower material cost than phosphorescent metal complexes. The compound can be built into a stack structure of organic optoelectronic device, such as OLED. The resultant organic optoelectronic device includes an anode, a cathode, and at least one organic thin film located between the anode and the cathode, the organic thin film contains the compound as shown in Formula (I).

By providing a novel polycyclic aromatic compound in which a plurality of aromatic rings are linked via a boron atom, a nitrogen atom, or the like, options of a material for an organic EL element are increased. In addition, by using the novel polycyclic aromatic compound as a material for an organic electroluminescent element, an excellent organic EL element is provided.

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 invention relates to a process for preparing substituted biphenyls via Suzuki coupling using specific phosphorus ligands and a solvent mixture containing water, a non-polar organic solvent and a polar aprotic co-solvent.

By providing a novel polycyclic aromatic compound in which a plurality of aromatic rings are linked via a boron atom, a nitrogen atom, or the like, options of a material for an organic EL element are increased. In addition, by using the novel polycyclic aromatic compound as a material for an organic electroluminescent element, an excellent organic EL element is provided.