The invention relates to Rh, Ru, Co and Ir complexes comprising bidentate diphosphoramidites as ligands and to the use thereof as catalysts for the hydroformylation of olefins. The invention also relates to a process for preparing an aldehyde from an olefin using the complexes or ligands mentioned.

The present invention is intended to provide a method for efficiently producing and providing a compound having a spirooxindole skeleton, for example, a compound having a spirooxindole skeleton and having antitumor activity that inhibits the interaction between Mdm2 protein and p53 protein, or an intermediate thereof, using an asymmetric catalyst. A compound having an optically active tricyclic dispiroindole skeleton is efficiently obtained through a catalytic asymmetric 1,3-dipolar cycloaddition reaction using ketimine as a reaction substrate and using a chiral ligand and a Lewis acid.

The disclosure is directed to: (a) phosphacycle ligands; (b) catalyst compositions comprising phosphacycle ligands; and (c) methods of using such phosphacycle ligands and catalyst compositions in bond forming reactions.

Disclosed in the present invention are a camptothecin derivative intermediate, and a preparation method therefor and the use thereof. The structural formula of the camptothecin derivative intermediate of the present invention is as shown in formula (I), and the definition of each substituent is as described in the description and claims. The intermediate (I) of the present invention can be used for preparing an intermediate (III), and can be further used for preparing exatecan and a derivative thereof. The preparation method of the present invention has the advantages of cheap and easily available raw materials, a novel method and simple route, mild conditions, a high yield, few by-products, suitability for scale-up synthesis and industrial production, etc.

##STR00001##

A catalytic compound of formula I, II, or III is described; wherein M is selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; R.sup.1, N is an integer from 1 to 3; R.sup.2, R.sup.3, and R.sup.4 are independently selected from lower alkyl, lower alkoxy, C.sub.5-C.sub.8 aryl, and NR.sup.6.sub.2, wherein R.sup.6 is CH.sub.3 or C.sub.2H.sub.5; and R.sup.5 is selected from H, lower alkyl, lower alkoxy, and benzylic. Methods of using the compound to catalyze the formation of polylactides, and polylactides prepared using these methods are also described.

In one embodiment, the present application discloses mixtures comprising (a) water in an amount of at least 1% wt/wt of the mixture; (b) a transition metal catalyst; and (c) one or more solubilizing agents; and methods for using such mixtures for performing transition metal mediated bond formation reactions.

In one embodiment, the present application discloses mixtures comprising (a) water in an amount of at least 1% wt/wt of the mixture; (b) a transition metal catalyst; and (c) one or more solubilizing agents; and methods for using such mixtures for performing transition metal mediated bond formation reactions.

Use of a unique supramolecular assembly of a tris-pyridylphosphine ligand and a metal centered porphyrin complex modified with a lactone functional group was shown to have improved selectivities to branched aldehydes via rhodium catalyzed hydroformylation of unsubstituted linear alpha olefins such as propylene and 1-octene. The addition of potassium salts was also shown to increase the activity of the lactone modified porphyrin-based catalyst while maintaining similar branched aldehyde selectivities for propylene hydroformylation.

A zinc complex characterized in exhibiting an octahedral structure and being configured from repeating units represented by general formula (I): ##STR00001##
wherein L represents a linker region, and R.sup.1 represents a C1-4 alkyl group, which can have a halogen atom.

The present invention relates to a process for the oligomerisation of ethylene which comprises contacting ethylene with a transition metal-permethylpentalene complex, and a transition metal compound utilized therein.