Bimetallic catalytic binuclear elimination reaction experimental, spectroscopic and kinetic elucidation

BIMETALLIC CATALYTIC BINUCLEAR ELIMINATION REACTION. EXPERIMENTAL, SPECTROSCOPIC AND KINETIC ELUCIDATION LI CHUANZHAO NATIONAL UNIVERSITY OF SINGAPORE 2003 BIMETALLIC CATALYTIC BINUCLEAR ELIMINATION REACTION. EXPERIMENTAL, SPECTROSCOPIC AND KINETIC ELUCIDATION LI CHUANZHAO (B.Eng., M. Eng., Tianjin University) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF CHEMICAL & ENVIRONMENTAL ENGINEERING NATIONAL UNIVERSITY OF SINGAPORE 2003 ACKNOWLEDGEMENTS I am full of gratitude to my supervisor, Prof. Marc Garland for his insight, invaluable guidance, inspiring discussions and continuous supervision during my graduate study. He has always been great helpful and encouraging. He sets an exemplar in my future research. I would like to thank Prof A.K. Ray and Prof H.C. Zeng for their help and kindness. I wish to thank my colleagues in Prof Garland’s group, especially Dr Widjaja Effendi, Dr Chen Li and Mr Guo Liangfeng, who provided strong support for chemometrics analyses. Many thanks to Mr Chew Wee, Mr Liu Guowei, Ms Gao Feng and Ms Zhao Yanjun for their help. I would thank my wife, Mdm Wang Xiujuan, for her continuous support, encouragement and willingness to share my anxieties and joy of success. I am greatly indebted to the National University of Singapore for providing Postgraduate Research Scholarship and President’s Graduate Fellowship. Part of this project was sponsored by IBM and Institute for High Performance Computing (IHPC) for the High Performance Computing Quest (HPCQuest 2003). Finally, this thesis is dedicated to my daughter Li Chen. i TABLE OF CONTENTS ACKNOWLEDGEMENTS i CONTENTS ii SUMMARY xi NOMENCLATURE xiii LIST OF FIGURES xviii LIST OF TABLES xxvi Chapter INTRODUCTION Chapter LITERATURE REVIEW 2.1 Synergism in homogeneous catalysis 2.2 Binuclear elimination reaction 11 2.3 Catalytic binuclear elimination reaction 16 2.4 Hydroformylation 19 2.4.1 Catalysts 21 2.4.2 Unmodified rhodium catalyzed hydroformylation 21 2.4.2.1 Mechanism 22 2.4.2.2 Kinetics 25 2.4.3 Bimetallic hydroformylation Chapter 27 2.5 Total algebraic system identification 28 2.6 Summary 30 EXPERIMENTAL AND METHODOLOGY 32 3.1 32 Introduction ii 3.2 Experimental section 33 3.2.1 General information 33 3.2.2 Chemicals 33 3.2.3 Experimental apparatus and procedure 34 3.2.3.1 Photo-irradiation 34 3.2.3.2 In situ FTIR 36 3.3 Total algebraic system identification 40 3.3.1 Introduction 40 3.3.2 Algorithm for total algebraic system identification 41 3.3.2.1 Getting the experimental spectral data 41 3.3.2.2 Lambert-Beer-Bouguer Law 41 3.3.2.3 Singular value decomposition 42 3.3.2.4 Pure component spectra reconstruction 43 3.3.2.5 Data-renormalization 44 3.3.2.6 Real spectral absorptivities and mole numbers 45 3.4 Application of total algebraic system identification algorithm to 48 a semi-batch homogeneous catalytic reaction 3.4.1 Introduction 48 3.4.2 Experimental work 48 3.4.3 Results and discussion 50 3.4.3.1 Spectral analysis 50 3.4.3.2 SVD results 51 3.4.3.3 Pure component spectra reconstruction 54 3.4.3.4 Data-renormalization 61 3.4.3.5 Real IR absorptivities and mole numbers 61 iii 3.4.4 Discussion 3.5 Application of total algebraic system identification algorithm to 64 65 a homogeneous stoichiometric reaction Chapter 3.6 Summary 65 Rh4(CO)12/HMn(CO)5 BIMETALLIC CATALYZED 67 HYDROFORMYLATION OF 3,3-DIMETHYLBUT-1-ENE 4.1 Introduction 67 4.2 Experimental section 68 4.2.1 Pre-hydroformylation 68 4.2.2 Hydroformylation 69 4.3 Spectral analysis for pre-hydroformylation 72 4.4 Spectral analysis for hydroformylation 72 4.4.1 Data pe-processing 73 4.4.2 Preconditioning 73 4.4.3 Baseline correction 75 4.4.4 Total algebraic system identification 76 4.5 Experiment results 4.5.1 Spectral aspects 84 84 4.5.1.1 Pre-hydroformylation 84 4.5.1.2 Hydroformylation 84 4.5.2 Calculations 85 4.5.3 Results 87 4.5.3.1 With only Mn2(CO)10/HMn(CO)5 87 4.5.3.2 With Rh4(CO)12 and Mn2(CO)10/HMn(CO)5: 88 Changing HMn(CO)5 initial loadings iv 4.5.3.2.1 Initial reaction times 89 4.5.3.2.2 Product formation 93 4.5.3.2.3 TOF analyses 96 4.5.3.3 Changing Rh4(CO)12 initial loadings 97 4.5.3.3.1 Initial reaction times 98 4.5.3.3.2 Product formation 102 4.5.3.3.3 TOF analyses 104 4.5.3.4 Changing 33DMB initial loadings 105 4.5.3.4.1 Initial reaction times 106 4.5.3.4.2 Product formation 109 4.5.3.4.3 TOF analyses 111 4.5.3.5 Changing CO pressure 112 4.5.3.5.1 Initial reaction times 112 4.5.3.5.2 Product formation 116 4.5.3.5.3 TOF analyses 118 4.5.3.6 Changing H2 pressure 119 4.5.3.6.1 Initial reaction times 120 4.5.3.6.2 Product formation 124 4.5.3.6.3 TOF analyses 126 4.5.3.7 Changing Temperature 127 4.5.3.7.1 Initial reaction times 127 4.5.3.7.2 Product formation 131 4.5.3.7.3 TOF analyses 132 4.6 Catalysis and kinetics 133 4.6.1 Pre-catalytic 133 v 4.6.2 Hydroformylation 4.7 Discussion Chapter 137 142 4.7.1 Evidence for existence of CBER 142 4.7.2 Initial reaction times and precatalytic steps 145 4.7.3 Deactivation 146 4.8 Conclusion 146 Rh4(CO)12/HMn(CO)5 BIMETALLIC CATALYZED 148 HYDROFORMYLATION OF CYCLOPENTENE 5.1 Introduction 148 5.2 Experimental section 148 5.3 Spectral analyses 150 5.4 Experimental results 158 5.4.1 Spectral aspects 158 5.4.2 Calculations 158 5.4.3 Results 159 5.4.3.1 With only Mn2(CO)10/HMn(CO)5 159 5.4.3.2 With Rh4(CO)12 and Mn2(CO)10/HMn(CO)5: 159 Changing HMn(CO)5 initial loadings 5.4.3.2.1 Initial reaction times 160 5.4.3.2.2 Product formation 164 5.4.3.2.3 TOF analyses 166 5.4.3.3 Changing Rh4(CO)12 initial loadings 167 5.4.3.3.1 Initial reaction times 168 5.4.3.3.2 Product formation 172 5.4.3.3.3 TOF analyses 174 vi 5.4.3.4 Changing CP initial loadings 175 5.4.3.4.1 Initial reaction times 176 5.4.3.4.2 Product formation 179 5.4.3.4.3 TOF analyses 181 5.4.3.5 Changing CO pressure 182 5.4.3.5.1 Initial reaction times 182 5.4.3.5.2 Product formation 185 5.4.3.5.3 TOF analyses 188 5.4.3.6 Changing H2 pressure 189 5.4.3.6.1 Initial reaction times 189 5.4.3.6.2 Product formation 192 5.4.3.6.3 TOF analyses 194 5.4.3.7 Changing Temperature 196 5.4.3.7.1 Initial reaction times 196 5.4.3.7.2 Product formation 199 5.4.3.7.3 TOF analyses 201 5.5 Catalysis and kinetics 202 5.5.1 Pre-catalytic 202 5.5.2 Hydroformylation 206 5.6 Discussion 209 5.6.1 Further evidence for existence of CBER 209 5.6.2 Initial reaction times and precatalytic steps 212 5.7 Conclusion 213 vii Chapter THE Rh4(CO)12 CATALYZED HYDROFORMYLATION OF 215 CYCLOPENTENE PROMOTED WITH HRe(CO)5 6.1 Introduction 215 6.2 The identification of RhRe(CO)9 215 6.2.1 Experiments 215 6.2.2 Spectral analyses 218 6.2.3 Thermodynamics 228 6.2.4 Discussion 232 6.3 The Rh4(CO)12 catalyzed hydroformylation of cyclopentene 233 promoted with HRe(CO)5 6.3.1 Experimental section 233 6.3. Spectral analyses 235 6.3.3 Catalysis results 242 6.3.3.1 Spectra aspects 242 6.3.3.2 Calculations 242 6.3.3.3 Hydroformylation with only HRe(CO)5 242 6.3.3.4 Hydroformylation with Rh4(CO)12 and 243 HRe(CO)5 : Changing HRe(CO)5 initial loadings 6.3.3.4.1 Initial reaction times 244 6.3.3.4.2 Product formation 248 6.3.3.4.3 TOF analyses 250 6.3.3.5 Changing Rh4(CO)12 initial loadings 251 6.3.3.5.1 Initial reaction times 252 6.3.3.5.2 Product formation 256 6.3.3.5.3 TOF analyses 258 viii Oro, L. A. and E. Sola. Mechanistic aspects of dihydrogen activation and catalysis by dinuclear complexes. In Recent Advances in Hydride Chemistry. ed by Peruzzini, Maurizio and Poli, Rinaldo. pp. 299-327. 2001. Osborn, John A., F. Jardine, J. Young and G. Wilkinson. Preparation and properties of tris(triphenylphosphine)halorhodium(I) and some reactions thereof including catalytic homogeneous hydrogenation of olefins and acetylenes and their derivatives. J. Chem. Soc. A , 12,pp.1711-32 .1966. Pan, Y.Y. The Reconstruction of Pure Component Spectra in Exploratory Chemometric Studies. Entropy Minimizations and Large Scale Problems. M.Eng Thesis, National University of Singapore. 1999. Pan Y.; L. Susithra and M. Garland M. Pure Component Reconstructions using Entropy Minimizations and Variance-Weighted Piecewise-Continuous SpectralRegions. Application to the unstable experimental system Co2(CO)8/Co4(CO)12. Journal of Chemometrics , 14(2), 63-77. 2000. Puddephatt, R. J. Metal clusters in catalysis - an overview. in Metal Clusters in Chemistry, ed by Braunstein, Pierre; Oro, Luis A. and Raithby, Paul R. 2, pp 605-615. Weinheim: Wiley, 1999. 319 Reek, J. N. H.; P. Kamer and P.W.N.M. van Leeuwen. hydroformylation. Catalysis by Metal Complexes. Novel developments in 22(Rhodium Catalyzed Hydroformylation), pp.253-279. 2000. Renaut, P.; G. Tainturier and B. Gautheron. Formation of a zirconium-molybdenum bond via methane elimination. Journal of Organometallic Chemistry , 150(1), pp. C9-C10. 1978. Roelen, O. Organic carbonyl compounds such as aliphatic aldehydes. US 2327066 , 1943. Roelen, O. Synthesis of aldehydes and derivatives from olefins, carbon monoxide, and hydrogen. Angew. Chem. A60, pp. 62. 1948. Roelen, O. Invention of the Fischer-Tropsch synthesis. Erdoel & Kohle, Erdgas, Petrochemie . 31(11), pp. 524-9.1978. Sabatier, P.C. Applied Inverse Problems. Berlin: Springer-Verlag. 1978. Sbrignadello, G.; G. Bor and L. Maresca. Infrared spectroscopic studies on metal carbonyl compounds. XIV. Assignments in the C-O stretching region of the authentic infrared spectra of the compounds MCo(CO)9 (M = manganese or rhenium) and of the monosubstituted derivative MnCo(CO)8P(C6H5)3. Journal of Organometallic Chemistry 46(2), pp. 345-55. 1972. 320 Schiller, G. (Chem. Verwertungsges. Oberhausen), Catalyst for Oxo Synthesis. Ger. Pat. 953.605, 1956. Schwartz, J. and J. Cannon, Hydroacylation. Synthesis of ketones from olefins using metal hydride reagents. Journal of the American Chemical Society, 96(14), pp.47213.1974. Shannon, C.E. A Mathematical Theory of Communication. Bell System Tech. J. 3, pp. 379-423, 1948. Shriver, D.F. and M. A. Drezdzon, The manipulation of Air-Sensitive Compounds. New York: Wiley. 1986. Skirt, R.; M. Garland and D. Rippin. On the evaluation of turnover frequencies in unicyclic homogeneous catalysis. Experimental, numerical, and statistical aspects, Anal. Chim. Acta, pp. 67-91, 1998. Slivinskii, E. V.; G.A. Korneeva; N. Rzhevskaya; V. Kurkin; R. Aranovich and S. Loktev. Conversion of rhodium carbonyls during formation of an olefin hydroformylation catalyst from dodecacarbonyltetrarhodium. Neftekhimiya 30(1), 53-7.1990. 321 Stanley, G. G. Bimetallic homogeneous hydroformylation. in Catalysis by Di- and Polynuclear Metal Cluster Complexes, ed by Adams, Richard D. and Cotton, F. Albert. pp. 345-372. New York: Wiley-VCH. 1998. Sunley, G. J. and D. Watson. High productivity methanol carbonylation catalysis using iridium. The Cativa process for the manufacture of acetic acid. Catalysis Today ,58(4), pp.293-307.2000. Susithra, L. In-Situ Kinetic Studies of the Homogeneous Catalytic Hydroformylation with Unmodified Cobalt Carbonyls. M.Eng Thesis, National University of Singapore. 1999. Sweany, Ray; S. Butler and J. Halpern, The hydrogenation of 9,10-dimethylanthracene by hydridopentacarbonylmanganese(I). Evidence for a free-radical mechanism. Journal of Organometallic Chemistry .213(2), pp. 487-92 .1981. Thurston, T.J. and R.G. Brereton. Estimation of Second Order Rate Constants Using Chemometric Methods with Kinetic Constraints. Analyst. 127, pp. 659-668. 2002. Uccelo-Barretta, G.; R. Lazzaroni; R. Settambolo and P. Salvadori, The Use of 2H NMR in the Elucidation of the Catalytic Pathway of the Hydroformylaton Reaction J. Organomet. Chm., 417, pp. 111-119, 1991. Ungvary, F. and L. Marko, Stoichiometric hydrogenation of olefins with carbonyl hydride, Acta Chim Hung, pp.425-428, 1969. 322 Ungvary, F. and L. Marko, Kinetics and mechanism of the decomposition of cobalt tetracarbonyl hydride to dicobalt octacarbonyl and hydrogen . Journal of Organometallic Chemistry , 20(1), pp. 205-9. 1969. Ungvary, F. and L. Marko, Reaction of HCo(CO)4 and CO with styrene. Mechanism of (phenylpropionyl)- and (phenylpropionyl)cobalt tetracarbonyl formation. Organometallics , 1(9), pp.1120-5. 1982. Ungvary, F. and L. Marko, Kinetics and mechanism of ethyl formate formation from (ethoxycarbonyl)cobalt tetracarbonyl and molecular hydrogen or HCo(CO)4. Organometallics , 2(11), pp.1608-12. 1983. Van Eldik, R.; T. Asano and W. Le Noble, Activation and reaction volumes in solution. 2. Chemical Reviews (Washington, DC, United States), 89(3), pp.549-688. 1989. Van Hoven M. N. H. Alemdaroglu, and J.M. L. Penninger, Hydroformylation with Cobalt Carbonyl and Cobalt Carbonyl tributylphosphosphine Catalysts, Ind, Eng. Chem. Prd. Res. Dev., 14, pp.259, 1975. Van Leeuwen, P.W.N.M. in Rhodium catalyzed hydroformylation ed by Van Leeuwen P.W.N.M. and C. Claver, Chapter 1, 1-15. Boston: Kluwer Academic Publishers, 2000. 323 Vidal, J. L. and W.E. Walker, Rhodium Carbonyl Cluster Chemistry under High Pressure of Carbon Monoxide and Hydrogen. 3. Synthesis, Characterization, and Reactivity of HRh(CO)4, Inorg. Chem., 20, PP. 249-254, 1981. von Brandes, K. H. and H.B. carbonyl. Jonassen. Thermal decomposition of cobalt-hydrogen Zeitschrift fuer Anorganische und Allgemeine Chemie, 343(3-4), pp. 215-19. 1966. Wassink, B.; M. Thomas; S. Wright; D. Gillis and M. Baird, Mechanisms of the hydrometalation (insertion) and stoichiometric hydrogenation reactions of conjugated dienes effected by manganese pentacarbonyl hydride: processes involving the radical pair mechanism. Journal of the American Chemical Society 109(7), pp.1995-2002. 1987. Weinheim, J. F. H. In-situ spectroscopy in heterogeneous catalysis / edited by James F. Haw. Cambridge : Wiley-VCH. pp1-14, 2002. Whyman, R. Tetranuclear and Dinuclear Phophine-and Arsine- Substituted Rhodium Carbonyl. J. Chem. Soc., Dalton Trans. 13, pp. 1375-1381. 1972. Whyman R. Laboratory Methods in Vibrational Spectroscopy, 3rd ed ed. By Willis H.A., Van der Maas J.H. and Miller R.G.J., Chapter 12, Wiley, New York: Wiley, 1987. Whyman, R. In situ spectroscopic studies in homogeneous catalysis. In Advances in Chemistry Series, 230 (Homogeneous Transition Met. Catal. React.), pp19-31. 1992. 324 Whyman, R. in Rhodium Catalyzed Hydroformylation, ed by P. W. N. M. van Leeuwen and C. Claver. Applied Organometallic Chemistry, 15(4), pp.315-316. 2001. Whyman, R.; A. Wright, J. Iggo and B.T. Heaton, Carbon monoxide activation in homogeneously catalysed reactions: the nature and roles of catalytic promoters. Journal of the Chemical Society, Dalton Transactions. (5), pp.771-777.2002. Widjaja, E.; C. Li and M. Garland, Semi-Batch Homogeneous Catalytic In-Situ Spectroscopic Data. FTIR Spectral Reconstructions Using Band-Target Entropy Minimization (BTEM) without Spectral Preconditioning. Organometallics ,21(9), pp.1991-1997. 2002. Widjaja, E. and M. Garland. Pure Component Spectral Reconstruction from Mixture Data using SVD, Global Entropy Minimization and Simulated Annealing. Numerical Investigations of Admissible Objective Functions Using a Synthetic 7-Species Data Set. J. Comput. Chem. 23, pp. 911-919. 2002. Widjaja, E., C. Li and M. Garland. Total Algebraic System Identification for Homogeneous Catalyzed Syntheses of Fine Chemicals. Proceeding of the International Conference on Scientific & Engineering Computation (IC-SEC), pp. 36-40. London: Imperial College Press. 2002. 325 Widjaja, E.; C. Li; W. Chew and M. Garland, Marc. Band-Target Entropy Minimization. A Robust Algorithm for Pure Component Spectral Recovery. Application to Complex Randomized Mixtures of Six Components. Analytical Chemistry ACS ASAP. 2003. Widjaja, E. Band-Target Entropy Minimization and Associated Software Tools. PhD Thesis, National University of Singapore, 2003. Yagupsky, G.; C. Brown and G. hydridocarbonyltris(triphenylphosphine)rhodium(I); Wilkinson. Studies on intermediate species in hydroformylation; rhodium and iridium analogs. J. Chem. Soc. A 9, pp.1392-401. 1970. Zhang, H.; Y. Zeng; P. Wu and M. Garland. Pure-component mass spectrum reconstruction with two-band target entropy minimization: Application to mass spectral data. Abstracts of Papers, 225th ACS National Meeting, New Orleans, LA, United States, March 23-27, 2003. Zhang, J.; M. Poliakoff Alkenes Using in and M. George. Rhodium-Catalyzed Hydroformylation of Situ High-Pressure IR and Polymer Matrix Techniques. Organometallics 22(8), pp.1612-1618.2003. Zeng, Y.Z. and M. Garland. An improved algorithm for estimating pure component spectra in exploratory chemometic studies based on entropy minimisation. Anal. Chim. Acta. 359, pp.303-310, 1998. 326 Appendix A 327 328 329 330 Appendix B HOMOGENEOUS BIMETALLIC CATALYZED HYDROFORMYLATION OF ALKENES B.1 Rh4(CO)12/HMn(CO)5 bimetallic catalyzed hydroformylation of methylenecyclohexane Two preliminary experiments were performed at 2.0MPa CO, 2.0 MPa H2, 289K, with 2.0ml methylenecyclohexane in 300 ml n-hexane. The initial loadings were: 52.28 mg Rh4(CO)12 for pure rhodium system and 18.08 mg Rh4(CO)12 and 425.3mg Mn2(CO)10 for Rh/Mn bimetallic system. In situ FTIR spectral analyses found only four observable organometallic species, namely Rh4(CO)12, HMn(CO)5, Mn2(CO)10 and RCORh(CO)4. The product formation rate in Rh/Mn(18.08 mg Rh4(CO)12 ) bimetallic hydroformylation is circa 20% higher than when 52.28 mg Rh4(CO)12 was used alone. B.2 Rh4(CO)12/HMn(CO)5 bimetallic catalyzed hydroformylation of styrene Two preliminary experiments were performed at 5.0MPa CO, 0.5 MPa H2, 303K, with 25.0 ml styrene in 300 ml n-hexane. The initial loadings were: 96.0 mg Rh4(CO)12 for pure rhodium system and 99.5 mg Rh4(CO)12 and 187.5 mg Mn2(CO)10 for Rh/Mn bimetallic system. In situ FTIR spectral analyses found only four observable organometallic species, namely Rh4(CO)12, HMn(CO)5, Mn2(CO)10 and RCORh(CO)4. The product formation rate in Rh/Mn bimetallic hydroformylation is circa 90% higher than when Rh4(CO)12 was used alone. 331 B.3 Rh4(CO)12/HRe(CO)5 bimetallic catalyzed hydroformylation of styrene Two preliminary experiments were performed at 5.0MPa CO, 0.5 MPa H2, 303K, with 25.0 ml styrene in 300 ml n-hexane. The initial loadings were: 91.2 mg Rh4(CO)12 for pure rhodium system and 82.16 mg Rh4(CO)12 and circa 10 µL HRe(CO)5 for Rh/Re bimetallic system. In situ FTIR spectral analyses found four observable organometallic species, namely Rh4(CO)12, HRe(CO)5, RhRe(CO)9 and RCORh(CO)4. The product formation rate in Rh/Re bimetallic hydroformylation is circa 150% higher than when Rh4(CO)12 was used alone. B.4 Rh4(CO)12/HRe(CO)5 bimetallic catalyzed hydroformylation of methylenecyclohexane Two preliminary experiments were performed at 2.0MPa CO, 2.0 MPa H2, 289.7 K, with 2.0 ml methylenecyclohexane in 300 ml n-hexane. The initial loadings were: 52.28 mg Rh4(CO)12 for pure rhodium system and 40.31 mg Rh4(CO)12 and circa 20 µL HRe(CO)5 for Rh/Re bimetallic system. In situ FTIR spectral analyses found four observable organometallic species, namely Rh4(CO)12, HRe(CO)5, RhRe(CO)9 and RCORh(CO)4. The product formation rate in Rh/Re bimetallic hydroformylation is circa 210% higher than when Rh4(CO)12 was used alone. 332 LIST OF PUBLICATIONS Chuanzhao Li, Effendi Widjaja, Wee Chew and Marc Garland. Rhodium Tetracarbonyl Hydride: The Elusive Metal Carbonyl Hydride. Angewandte Chemie (Int.Ed.) Vol 41,No 20, 3785-3789 (2002). Chuanzhao Li, Effendi Widjaja, and Marc Garland. Bimetallic Catalytic Binuclear Elimination - an Origin of Synergism in Homogeneous Catalysis. Journal of The American Chemical Society, 125(18), 5540-5548(2003). Chuanzhao Li, Effendi Widjaja , and Marc Garland . Spectral Reconstruction of In-Situ FTIR Spectroscopic Reaction Data Using Band-Target Entropy Minimisation (BTEM).Application to the Homogeneous Rhodium Catalyzed Hydroformylation of 3,3Dimethylbut-1-ene using Rh4(CO)12, Journal of Catalysis, Vol 213, 126-134( 2003). Effendi Widjaja, Chuanzhao Li, and Marc Garland. Semi-Batch Homogeneous Catalytic In-Situ Spectroscopic Data. FTIR Spectral Reconstructions Using Band-Target Entropy Minimisation (BTEM) without Spectral Preconditioning. Organometallics, 21,1990-1997 (2002). Effendi Widjaja, Chuanzhao Li, and Marc Garland. Total Algebraic System Identification for Homogeneous Catalyzed Syntheses of Fine Chemicals. Proceeding of the International Conference on Scientific & Engineering Computation (IC-SEC), Recent Advances in Computational Sciences and Engineering. Ed. by Lee, H. P. and K. Kumar. P36-40. London: Imperial College Press. 2002. Effendi Widjaja, Chuanzhao Li ,Wee Chew and Marc Garland. BTEM-A Robust Algorithm for pure spectral recovery. Application to Complex Randomized Mixtures of Six Components Analytical Chemistry, 75, 4499-4507, 2003. Effendi Widjaja, Chuanzhao Li and Marc Garland. Algebraic System Identification. Journal of Catalysis, in press , 2004. 333 Chuanzhao Li, Laingfeng Guo and Marc Garland. Rhodium catalyzed hydroformylation of Ethylene: Identification of a new metal carbonyl. Organometallics, revised, 2003. Chuanzhao Li, Effendi Widjaja and Marc Garland. Bimetallic hydroformylation of cyclopentene: a further evidence on higher order catalysis. submitted to Organometallics.2003. Chuanzhao Li, Li Chen, Marc Garland. Bimetallic hydroformylation of cyclopentene with HRe(CO)5 /Rh4(CO)12: a futher evidence on bimetallic CBER. To be submitted. Chuanzhao Li, Liangfeng Guo and Marc Garland. Deactivation of Rhodium during the hydroformylation of 4VP. In preparation. Chuanzhao Li, Effendi Widjaja and Marc Garland. Reinvestigation of the hydroformylation of butyne catalyzed with rhodium. In preparation. 334 [...]... mediated strategies, non-linear catalytic kinetics and higher efficiency (TOF) and chemical selectivity In particular, although the existence of binuclear elimination reactions associated with the hydroformylation reaction has been clearly demonstrated in the stoichiometric case, solid experimental, mechanistic and kinetic evidence for catalytic binuclear elimination under catalytic conditions has been... stoichiometric binuclear elimination between mononuclear complexes leading to the elimination of a new organic product and the formation of a dinuclear complex has been well documented This rather rare reaction is reviewed as well as the concept of catalytic binuclear elimination reaction (CBER) Catalytic binuclear elimination is exceptionally interesting from both a synthetic as well as kinetic viewpoint and. .. attack on Rh4(CO)12 These spectroscopic and kinetic results strongly suggest that the origin of synergism is the presence of bimetallic catalytic binuclear elimination This appears to be the first detailed evidence for such a catalytic mechanism Accordingly, a reaction topology for the simultaneous interconnected unicyclic Rh and bimetallic Rh-Mn or Rh-Re CBER hydroformylation reactions was proposed xii... catalytic It is important to note that such a homogeneous catalytic system would consist of a non-trivial reaction topology with both mononuclear and dinuclear organometallic intermediates If two metallic elements are present, then the physical system would involve two sets of distinct mononuclear species and one set of bimetallic dinuclear complexes The bimetallic catalytic binuclear elimination reaction. .. effect of temperature on TOF 282 Figure 6.53 The proposed reaction topology for the simultaneous 291 interconnected unicyclic Rh and bimetallic Rh-Re CBER hydroformylation reactions xxv LIST OF TABLES Table Title Page Table 2.1 Homometallic stoichiometric binuclear elimination reaction 13 Table 2.2 Bimetallic stoichiometric binuclear elimination reaction 14 Table 3.1 Experimental design for a Single 11-step... to rationally search for and then identify a bimetallic catalytic binuclear elimination reaction The starting point will be the use of the well studied unmodified rhodium catalysed hydroformylation reaction Since metal carbonyl hydrides have been widely used in stoichiometic binuclear elimination reactions, we would use such metal hydrides as our second metal complex to see if bimetallic CBER could be... mononuclear complexes are known In this regard, the reactions between mononuclear complexes, leading to the fusion of two ligands, the formation of a dinuclear complex and simultaneous elimination of an organic product is particularly interesting The first example of such a reaction was observed by Breslow and Heck (1960), and the name "binuclear elimination reaction" has consequently been used(Jones et... precursors (Garland, 1993) and promoted abstraction in the I/Ru/Ir system (Sunley et al., 2000;Whyman et al., 2002) 1 Simple associative, dissociative and interchange reactions play a significant role in mechanistic organometallic chemistry (Langford et al., 1965), and much of this understanding has developed from the study of reactions between ligands and mononuclear complexes However, reactions between... frequencies(TOF) were investigated Accordingly, the kinetics and catalysis for the Rh/Mn bimetallic catalyzed hydroformylation were examined to search for evidence of bimetallic CBER Observable kinetics of the form Eq 1.5 was found This appears to be the first in-situ spectroscopic and kinetic evidence for bimetallic CBER In Chapter 5, the Rh4(CO)12/HMn(CO)5 bimetallic catalyzed hydroformylation was extended... of alkenes A total of seven bimetallic systems (Rh/Mn/3,3-dimethylbut-1-ene(33DMB), Rh/Mn/Cyclopentene, Rh/Mn/styrene, Rh/Mn/methylenecyclohexane, Rh/Re/Cyclopentene, Rh/Re/Styrene, and Rh/Re/Methylenecyclohexane) have been studied to seek for the bimetallic catalytic binuclear elimination reaction( CBER) In the next three chapters (Chapter 4, Chapter 5 and Chapter 6), three bimetallic systems (Rh/Mn/33DMB, . BIMETALLIC CATALYTIC BINUCLEAR ELIMINATION REACTION. EXPERIMENTAL, SPECTROSCOPIC AND KINETIC ELUCIDATION LI CHUANZHAO . NATIONAL UNIVERSITY OF SINGAPORE 2003 BIMETALLIC CATALYTIC BINUCLEAR ELIMINATION REACTION. EXPERIMENTAL, SPECTROSCOPIC AND KINETIC ELUCIDATION LI CHUANZHAO. the concept of catalytic binuclear elimination reaction (CBER). Catalytic binuclear elimination is exceptionally interesting from both a synthetic as well as kinetic viewpoint and it would constitute