Novel processes of preparing block polyester copolymers while precisely controlling the stereoconfiguration (e.g., tacticity), chemical composition and/or length of each unit (block) are provided. Block polyester copolymers featuring desirable combinations of two or more blocks featuring different stereoconfiguration (e.g., tacticity), chemical composition and/or length, including triblock, tetrablock and higher block copolymers are also provided. A novel family of organometallic magnesium complexes and uses thereof in preparing polyesters and block polyester copolymers are also provided.

Disclosed herein are a chromium compound represented by Formula 1a or 1c and a catalyst system including the same, exhibiting superior catalytic activity in an olefin trimerization reaction:
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)][Formula 1a]
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)].sub.4.2H.sub.2O.[Formula 1c]

Methods of synthesizing compounds comprising fluorinated aryl groups are disclosed, wherein said methods utilize hydrogen bond directed photocatalytic hydrodefluorination.

An oxidative homocoupling method of synthesizing certain 2,2-bithiophenes from thiophenes using oxygen as the terminal oxidant is disclosed. In non-limiting examples, the method uses oxygen along with a catalytic system that includes palladium, an assistive ligand, and a non-palladium metal additive to catalyze one of the following reactions: ##STR00001## Associated catalytic systems and compositions are also disclosed.

Methods of synthesizing and isolating facial-tris-homoleptic phenylpyridinato iridium (III) photocatalysts are disclosed. Also disclosed are methods of recovering excess 2-phenylpyridine ligands from said syntheses.

This invention relates generally to olefin metathesis catalyst compounds, to the preparation of such compounds, compositions comprising such compounds, methods of using such compounds, articles of manufacture comprising such compounds, and the use of such compounds in the metathesis of olefins and olefin compounds. The invention has utility in the fields of catalysts, organic synthesis, polymer chemistry, and industrial and fine chemicals industry.

Novel processes of preparing block polyester copolymers while precisely controlling the stereoconfiguration (e.g., tacticity), chemical composition and/or length of each unit (block) are provided. Block polyester copolymers featuring desirable combinations of two or more blocks featuring different stereoconfiguration (e.g., tacticity), chemical composition and/or length, including triblock, tetrablock and higher block copolymers are also provided. A novel family of organometallic magnesium complexes and uses thereof in preparing polyesters and block polyester copolymers are also provided.

This invention relates generally to olefin metathesis catalyst compounds, to the preparation of such compounds, compositions comprising such compounds, methods of using such compounds, articles of manufacture comprising such compounds, and the use of such compounds in the metathesis of olefins and olefin compounds. The invention has utility in the fields of catalysts, organic synthesis, polymer chemistry, and industrial and fine chemicals industry.

A homogeneous catalytic reaction method and a catalyst for isomerization and hydroformylation of long-chain internal olefins are disclosed. A rhodium-ruthenium metal complex is used as a catalyst; and the ligands are tetradentate phosphine ligands. By means of the catalytic system, homogeneous internal olefin isomerization aid hydroformylation can be performed under a certain temperature and pressure to obtain aldehyde products having high normal to iso ratios. The present invention is applicable to not only long-chain internal olefins (C8) but also internal olefins having a carbon number less than 8.

Some embodiments of the invention include methods of using a compound (e.g., Formula (I)) for the reduction of carbon dioxide to formate by contacting the carbon dioxide with a composition comprising a compound. In certain embodiments, the source of the carbon dioxide is air or is flue gas. Additional embodiments of the invention are also discussed herein.