The present invention relates to a ligand compound, a catalyst system for olefin oligomerization, and a method for olefin oligomerization using the same. The present ligand compound is a compound having a certain new structure and enables provision of a catalyst system for olefin oligomerization that can oligomerize ethylene with higher catalytic activity.

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 selective oligomerization of ethylene to produce a mixture comprising octene and hexene is conducted in the presence of a catalyst system comprising a source of chromium; two different P—N—P ligands and an activator. The phosphorus atoms of both ligands have ortho-fluoro phenyl substituents. The nitrogen atom of the first ligand has an isopropyl substituent. The nitrogen of the second ligand has a larger/bulkier hydrocarbyl substituent on the N atom. The hexene produced by the process of this invention has very high alpha selectivity.

The present invention relates to a ligand compound, a catalyst system for oligomerization of olefins including the ligand compound and the organic chromium compound, and a method for oligomerizing olefins using the same. The catalyst system for olefin oligomerization according to the present invention invention exhibits high selectivity to 1-hexene or 1-octene while having excellent catalytic activity, thereby enabling more efficient production of alpha-olefins.

Disclosed herein is a method of preparing 1-octene at high activity and high selectivity while stably maintaining reaction activity by tetramerizing ethylene using a chromium-based catalyst system comprising a transition metal or a transition metal precursor, a cocatalyst, and a P—C—C—P backbone structure ligand represented by (R.sup.1)(R.sup.2)P—(R.sup.5)CHCH(R.sup.6)—P(R.sup.3)(R.sup.4).

The present invention provides a novel catalyst of formula (I): wherein M is selected from Zn(H), Co(II), Mn(II), Mg(II), Fe(II), Cr(III)—X or Fe(III)—X, and the use thereof in polymerising carbon dioxide and an epoxide.

N.sup.2-phosphinyl amidine compounds, N.sup.2-phosphinyl amidinates, N.sup.2-phosphinyl amidine metal salt complexes, N.sup.2-phosphinyl amidinate metal salt complexes are described. Methods for making N.sup.2-phosphinyl amidine compounds, N.sup.2-phosphinyl amidinates, N.sup.2-phosphinyl amidine metal salt complexes, and N.sup.2-phosphinyl amidinate metal salt complexes are also disclosed. Catalyst systems utilizing the N.sup.2-phosphinyl amidine metal salt complexes and N.sup.2-phosphinyl amidinate metal salt complexes are also disclosed along with the use of the N.sup.2-phosphinyl amidine compounds, N.sup.2-phosphinyl amidinates, N.sup.2-phosphinyl amidine metal salt complexes, and N.sup.2-phosphinyl amidinate metal salt complexes for the oligomerization and/or polymerization of olefins.

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.

The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.