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In recent years two-phase catalysis has been established as a new field of catalyzed processes and has achieved industrial-scale importance in olefin hydroformylation. Two-phase reactions have a number of advantages, for example, ease of separation of catalyst and product, catalysts can be tailored to the particular problem, use of special properties and effects of water as a solvent, and low environmental impact. For higher olefins (* C6), the reaction suffers low activity due to low water solubility of higher olefins. Tricesium analog of TPPTS, m,m,m-trisulfonated triphenylphosphine, was synthesized and fully characterized. Two-phase olefin hydroformylation with Rh(acac)(CO)2 was investigated. The results indicated that both activity and selectivity (linear to branch aldehyde ratio) are similar to Rh/TPPTS system. The salt effect showed that increase the solution ionic strength will increase the selectivity and decrease the activity in the olefin hydroformylation with TPPTS. A new surface active phosphine, trisulfonated tris-m-(3henylpropyl)phenylphosphine, was synthesized and fully characterized. The results of biphasic olefin hydroformylation were consistent with aggregation of the ligand. The two phase 1-octene hydroformylation results showed that with only 3 methylene groups, there is no difference between the para and meta position of C3 group. A new chelating diphosphine, tetrasulfonated 2,2'-bis{di[p-(3 phenylpropyl)phenyl]phosphinomethyl}-1,1'-biphenyl,was prepared and fully characterized. Its application in two-phase hydroformylation of olefin showed enhanced activity and selectivity compared to the non-chelated phosphine analog. Finally, homogeneous asymmetric hydrogenation was carried out in the presence of a chiral surfactant in an attempt to affect asymmetric induction. The catalytic results showed that at a surfactant/Rh ratio of 25, the asymmetric hydrogenation of AACA-Me (a-Acetamidocinnamic Acid Methyl Ester) in methanol has no effect on asymmetric induction with the introduction of this chiral surfactant. / Master of Science

Two main areas are considered in this manuscript. The first describes the synthesis of group 10 metal complexes incorporating the water-soluble 1,3,5-triaza-7-phosphaadamantane (PTA) ligand and the second deals with the preparation of Cr(salen)X catalysts for the copolymerization of CO2 and epoxides. In the first topic, the synthesis of nickel(II) and palladium(II) salicylaldiminato complexes incorporating PTA has been achieved employing two preparative routes. Upon reacting the original ethylene polymerization catalyst developed by Grubbs and coworkers (Organometallics, 1998, 17, 3149), (salicylaldiminato)Ni(Ph)PPh3, with PTA using a homogeneous methanol/toluene solvent system resulted in the formation of the PTA analogs in good yields. Alternatively, complexes of this type may be synthesized via a direct approach utilizing (TMEDA)M(CH3)2 (M = Ni, Pd), the corresponding salicylaldimine, and PTA. Polymerization reactions were attempted using the nickel-PTA complexes in a biphasic toluene/water mixture in an effort to initiate ethylene polymerization by trapping the dissociated phosphine ligand in the water layer, thereby, eliminating the need for a phosphine scavenger. Unfortunately, because of the strong binding ability of the small, donating phosphine (PTA) as compared to PPh3, dissociation did not occur at a temperature where the complexes are not subjected to decomposition. Additionally, the unexplored PTA derivative, 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane (DAPTA), prepared by the literature procedure, was fully characterized by NMR and X-ray analysis. DAPTA is found be similar to its parent (PTA) in coordination mode and binding strength, as supported by its representative group 6 and group 10 complexes The second main topic involves the copolymerization of CO2 and epoxides (i.e., cyclohexene oxide (CHO)) for the formation of polycarbonate using Cr(salen)X (X = Br, OPh) catalysts with one equivalent of PR3 as the co-catalyst. The use of these catalysts and cocatalysts results in the most active chromium-based catalytic systems to date. The . hr-1highest activities observed are on the order of 109 mol CHO consumed . mol Cr-1 using PCy3 as the co-catalyst, and is clearly seen in the in situ monitoring of copolymer formation. An advantage of these systems involves the lack of cyclic carbonate production and high CO2 incorporation (>99%) within the polymer.