Abstract: A novel dinuclear metallocene complex is disclosed, which is represented by the following formula (I): wherein M1 and M2 are the same or different and are independently selected from the group consisting of Group IIIB, Group IVB and Group VB transition metals; each X is the same or different and is indepedently an anionic ligand with −1 valence, which is selected from the group consisting H, C1-20 hydrocarbyl, halogen, C1-20 alkoxy, C1-20 aryloxy, NH2, NHR11, NR11R12, —(C═O)NH2, —(C═O)NHR13, and —(C═O)NR13R14, wherein R11, R12, R13 and R14 are C1-20 alkyl; i is an integer from 1 to 3; j is an integer from 1 to 3, R1, R2, R3, R4, R5, R6, R7, and R8 are the same or different and are independently H, a C1-20 linear, branched or cyclic hydrocarbyl group, or a C2-4 cyclic hydrocarbylene group which forms a C4-6 fused ring system; Y1 and Y2 are the same or different and each is an electron-donating group independently selected from a Group 15 or Group 16 elem

Abstract: The present invention discloses an improved catalyst composition for preparing 5-formylvalerate esters by hydroformylation of pentenoic esters monoxide with good activity, high selectivity in the presence of hydrogen and carbon.

Abstract: A catalyst composition for the preparation of 3-pentenoic ester from butadiene. The catalyst composition includes a palladium complex; and a bidentate phosphine with the following formula: .sub.1 R.sub.2 P--(CH.sub.2)n--PR.sub.3 R.sub.4, wherein n is a integer from 1 to 6; and a bulky benzoic carboxylic acid.