In situ spectroscopic of the early events in the rodium mediated pauson khand reaction 2

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In situ spectroscopic of the early events in the rodium mediated pauson khand reaction 2

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APPENDIX A EXPERIMENTAL SETUP Appendix A Experimental Setups A.1 High-Pressure Setup Pressure transducer Gas purification columns Pump Vacuum Line Reservoir High pressure Flow through cell Stirrer Autoclave FTIR Cryostat Figure A.1 High pressure in-situ FTIR apparatus 243 APPENDIX A EXPERIMENTAL SETUP A.2 Low-Pressure Setup Pressure transducer To FTIR Reactor Pump Liquid Inlet Figure A.2 High pressure in-situ FTIR apparatus A.3 Vertex 70, Bruker MIR spectrometer. Lines to the reactor Liquid N2 dewar Flow through IR cell Figure A.3 Bruker MIR spectrometer. 244 APPENDIX A EXPERIMENTAL SETUP A.4 High Pressure Flow Through IR Cell a Thermal Fluid Inlet b Figure A.4 (a) Close up views of the flow through high pressure Cell and (b) Cell loaded into the IR compartment. 245 APPENDIX A EXPERIMENTAL SETUP A.5 n-hexane Refluxing Setup Condenser Heater L Bottomless Flask Figure A.5 Setup for n-hexane reflux 246 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster Appendix B Fluxionality Of Terarhodium Dodecarbonyl Cluster 247 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster 248 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster 249 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster 250 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster 251 APPENDIX B Fluxionality Of Tetrarhodium Dodecacarbonyl Cluster 252 APPENDIX E Butterfly Cluster Appendix E Butterfly Cluster: Organometallics 260 APPENDIX E Butterfly Cluster 261 APPENDIX E Butterfly Cluster 262 APPENDIX E Butterfly Cluster 263 APPENDIX E Butterfly Cluster 264 APPENDIX E Butterfly Cluster 265 APPENDIX E Butterfly Cluster 266 APPENDIX F On-Line FTIR Sonochemical Reaction Setup Appendix F On-Line FTIR Sonochemical Reaction Setup F.1 High-Pressure Setup Figure F.1 Sonochemical apparatus. Legend: 1. Ultrasonic power supply; 2. Converter; 3. Membrane pump; 4. Water bath. 267 APPENDIX G Preliminary FIR Analysis Appendix G Preliminary FIR Analysis The current appendix presents the first attempt of analyzing the far-infrared region. The collected spectra were obtain from monitoring the hydroformylation reaction of 3,3dimethy-l-butene was carried our using Rh4(CO)12 as the catalyst precursor, see scheme G.1. O CH3 + CO + H2 CH3 CH3 H H Scheme G.1 Hydroformylation of 3,3-dimethyl-1-butene. CH3 G.1 Experimental Setup The high pressure in-situ FTIR apparatus, described in chapter 3, Section 3.2.2, was used. However, the new cell described in chapter 5, section 5.5.1, KRS-5 windows was utilized in order to observe the region 400-1000 cm-1. G.2 Experimental Procedure First, background spectrum of the purged and empty IR sample chamber was recorded. Second, high pressure cell with KRS-5 windows was loaded into the IR compartment of the Perkin-Elmer SPECTRUM 2000 FT-IR spectrometer. Third, a 100 mL n-hexane was transferred under argon to the autoclave. Under MPa of CO gas, infrared spectra of the n-hexane in the high-pressure cell were recorded. Afterward, the stirrer and high-pressure membrane pump were started and a new spectrum was recorded. At the end of the initial steps described above, a solution of circa 50 mg Rh4(CO)9(μCO)3 dissolved in 50 mL n-hexane was prepared, transferred to the high-pressure reservoir under argon, pressurized and then added to the autoclave. After equilibration, infrared spectra of the Rh4(CO)9(μ-CO)3/dissolved gas/n-hexane solution in the highpressure cell were recorded. Afterward, solution of circa mL of 3,3-dimethy-l-but-ene dissolved in 50 mL n-hexane was prepared, transferred to the high-pressure reservoir 268 APPENDIX G Preliminary FIR Analysis under argon, pressurized and then added to the autoclave. Then, infrared spectra of the Rh4(CO)9(μ-CO)3/dissolved gas/n-hexane/3,3-dimethy-l-but-ene solution in the highpressure cell were recorded. Hydroformylation reaction was initiated by introducing MPa of H2 gas. Then, spectra were recorded at 10 minute intervals in the range 400-2500 cm-1. The semi-batch experiment lasted 14-hours and circa 70 spectra were collected. G.3 Far-infrared Region A representative spectra of the far-infrared region, 400-700 cm-1, are shown in Figure G.1. Figure G.1 In-situ raw far-infrared spectra of the hydroformylation of 3,3-dimethyl-1-but-ene in the range 400-700 cm-1. G.4 Spectra Analysis The collected spectra were consolidated into one matrix A 73×1501 . Then BTEM was used to reconstruct the pure component spectra present, see Figure G.2, following the same procedure described earlier in Chapter 3, Section 3.4.2-3. 269 APPENDIX G Preliminary FIR Analysis Figure G.2 The deconvoluted spectra of (a) Rh4(CO)9(μ-CO)3, (b) RCORh(CO)4, (c) 3,3-dimethyl-1-butene, and (c) aldehyde. 270 APPENDIX H DFT Improvements Appendix H DFT Improvements In the current section, the use of an appropriate basis set to describe the coordinated organic ligands, crabonyls, rather than just using DGDZVP to describe the entire cluster is investigated. This sort of investigation can be computationally expensive, thus, the study was carried on the relatively simple rhodium carbonyl hydride HRh(CO)4 as shown in Table H.1. Table H.1 Experimental and calculated vibrational wavenumbers (cm-1) for HRh(CO)4 and the corresponding deviation percentage (%) in Italic. Previous New Calculations DFT Method 6-31g 6-311g 6-311++g 6-311++g cc-pvqz DGDZVP (d) (d,p) (d,p) (3df,3pd) 1976 1987 1986 1968 1969 1969 (-1.34) (-0.79) (-0.84) (-1.74) (-1.69) (-1.69) 2044 2034 2025 2031 2028 2016 (0.12) (-0.37) (-0.81) (-0.52) (-0.67) (-1.25) 2066 2060 2054 2055 2053 2044 (-0.28) (-0.57) (-0.86) (-0.81) (-0.91) (-1.34) 2111 2107 2102 2106 2103 2093 (-0.59) (-0.78) (-1.02) (-0.83) (-0.97) (-1.44) Expt 2002.8 2041.6 2071.8 2123.6 It is quiet clear that used of 6-311g (d,p) to describe the organic ligand resulted in significant improvement in terms of the med-infrared prediction, crica 50% reduction in error, especially when compared to older calculations as shown in Figure H.1. d. Future work should further investigate wither such improvement can be achieved for larger clusters and if the new method improve the predicted geometrical parameters as well. 271 APPENDIX H DFT Improvements Figure H.1 Comparison between the theoretically predicted spectrum of HRh(CO)4 using (a) PBE/DGDZVP, (b) PBE/ DGDZVP [Rh]/6-311g (d,p) [C O] and (c) the experimentally observed spectrum after deconvolution. 272 PUBLICATIONS PUBLICATIONS International Refereed Journal Articles Allian, Ayman D. and Garland, Marc. Spectral resolution of fluxional organometallics. The observation and FTIR characterization of all-terminal [Rh4(CO)12]. Dalton Transactions, 11, pp. 1957-1965. 2005. Allian, Ayman D.; Tjahjono, Martin and Garland, Marc. Reaction of Alkynes with Rh4(CO)12. A Mid-Infrared Vibrational and Kinetic Study of (μ 4-η2-alkyne)Rh4(CO)8(μCO)2. Organometallics, 25(9), pp. 2182-2188. 2006. Allian, Ayman D.; Wang, Yezhong; Saeys, Mark; Kuramshina, Gulnara M. and Garland, Marc. The combination of deconvolution and density functional theory for the midinfrared vibrational spectra of stable and unstable rhodium carbonyl clusters. Vibrational Spectroscopy, 41(1), pp. 101-111. 2006. Allian, Ayman D.; Widjaja Effendi and Garland Marc. Experimental Raman spectra of dilute and laser-light-sensitive [Rh4(CO)9(µ-CO)3] and [(μ4-η2-3-hexyne)Rh4(CO)8(μCO)2]. Comparison with theoretically predicted spectra. Dalton Transactions, in press. Gao, Feng; Allian, Ayman D.; Zhang, Huajun; Cheng, Shuying and Garland, Marc. Chemical and kinetic study of acetophenone hydrogenation over Pt/Al2O3: Application of BTEM and other multivariate techniques to quantitative on-line FTIR measurements. Journal of Catalysis, 241(1), pp. 189-199. 2006. Gao, Feng, Ng, Kim Poi; Li, Chuanzhao; Krummel, Karl I.; Allian, Ayman D.; Garland, Marc. A versatile and compact experimental apparatus for the on-line spectroscopic study of liquid-phase heterogeneous catalytic systems. Journal of Catalysis, 237(1), pp. 49-57. 2006. 273 PUBLICATIONS Tjahjono, Martin; Allian, Ayman D. and Garland, Marc. The direct determination of partial molar volumes and reaction volumes in ultra-dilute non-reactive and reactive multi-component systems using a combined spectroscopic and modified response surface model approach. Dalton Transactions, 12, pp. 1505-1516. 2006. Allian, Ayman D.; Jacub, Chacko and Garland, Marc. 13C NMR study of the butterfly [(μ4η2-alkyne)Rh4(CO)8(μ-CO)2] cluster. (Manuscript in preparation) Allian, Ayman D. and Garland, Marc. Characterization of the (alkyne)Rh2(CO)6 and (alkyne)Rh2(CO)6. (Manuscript in preparation) Allian, Ayman D. and Garland, Marc. Characterization of new class of butterfly cluster; ([(enyne)Rh4(CO)7(μ-CO)2]. (Manuscript in preparation) Allian, Ayman D.; Tjahjono, Martin and Garland, Marc. In-situ mid-Infrared Vibrational and Kinetic Study of the fragmentation of the ([(1-heptyne)Rh4(CO)7(μ-CO)2. (Manuscript in preparation) Selected Conference Presentations Garland, Marc; Allian, Ayman D. Allian. In situ spectroscopic study of the fragmentation of tetrarhodium dodecacarbonyl under carbon monoxide. Abstracts of Papers, 227th ACS National Meeting, Anaheim, CA, United States, March 28-April 1, 2004. Allian, Ayman D.; Wee, Chew. Numerical treatment of in-situ data for the pre-catalytic transformations of rhodium carbonyl species and implications. AIChE Annual Meeting, Conference Proceedings, Austin, TX, United States, Nov. 7-12, 2004. Allian, Ayman D.; Tjahjono, Martin; Garland, Marc. Characterization of new rhodium complexes (μ 4-η2-hexyne)Rh4(CO)8(μ -CO)2: In situ FTIR investigation of the reaction of Rh4(CO)9(μ-CO)3 with monosubstituted/symmetric disubstituted alkynes under Argon and Carbon monoxide. Abstracts of Papers, 229th ACS National Meeting, San Diego, CA, United States, March 13-17, 2005. 274 PUBLICATIONS Allian, Ayman D.; Garland, Marc. Spectral resolution of fluxional organometallics: Further observations and experimental results for Rh4(CO)9(μ-CO)3. Abstracts of Papers, 229th ACS National Meeting, San Diego, CA, United States, March 13-17, 2005. Allian, Ayman D.; Wang, Yezhong; Saeys, Mark; Garland, Marc. Geometrical studies of isolatable and non-isolatable rhodium carbonyl clusters using mid-infrared vibrational spectra and density functional theory. Abstracts of Papers, 231st ACS National Meeting, Atlanta, GA, United States, March 26-30, 2006. Allian, Ayman D.; Tjahjono, Martin; Garland, Marc. Spectroscopic investigation of the butterfly cluster [(alkyne)Rh4(CO)10] and the kinetic of its formation. Abstracts of Papers, 231st ACS National Meeting, Atlanta, GA, United States, March 26-30, 2006. Tjahjono, Martin; Allian, Ayman D.; Li, Chuanzhao; Garland, Marc. Direct determination of the reaction volume of an organometallic reaction at very high dilution. AIChE Annual Meeting, Conference Proceedings, Austin, TX, United States, Nov. 7-12, 2004. Tjahjono, Martin; Allian, Ayman D.; Garland, Marc. Determination of limiting partial molar volumes of some organometallics from high dilution non reactive and reactive multi-component solutions. Abstracts of Papers, 229th ACS National Meeting, San Diego, CA, United States, March 13-17, 2005. 275 [...]... (-1.69) 20 44 20 34 20 25 20 31 20 28 20 16 (0. 12) (-0.37) (-0.81) (-0. 52) (-0.67) (-1 .25 ) 20 66 20 60 20 54 20 55 20 53 20 44 (-0 .28 ) (-0.57) (-0.86) (-0.81) (-0.91) (-1.34) 21 11 21 07 21 02 2106 21 03 20 93 (-0.59) (-0.78) (-1. 02) (-0.83) (-0.97) (-1.44) Expt 20 02. 8 20 41.6 20 71.8 21 23.6 It is quiet clear that used of 6-311g (d,p) to describe the organic ligand resulted in significant improvement in terms of the med-infrared... between the theoretically predicted spectrum of (μ4-η2HC2H)Co4(CO)8(μ-CO )2 using PBE/DGDZVP and the experimentally observed spectrum after deconvolution Table C .2 Predicted and experimental vibrational wavenumbers (cm-1) for (μ4- 2- HC2H)Co4(CO)8(μ-CO )2 Bridging Terminal CO stretches Expt 1879 20 00 20 23 20 40 20 43 20 53 20 93 DFT 1891 1999 20 09 20 29 20 32 2043 20 78 25 7 APPENDIX D RAMAN EXPERIMENTAL SETUP Appendix... 1.9 82 1.9 82 2.559 DFT 127 .5 119 .2 95.7 C7-C6-H1 Co4-C7-Co2 C 12- Co3-C5 Important distances Co1-Co2 Co2-Co4 Co3-C 12 C 12- O10 Co3-C1 C1-O5 Important angles Exp Co3-C1-O5 127 .3 Co1-Co2-Co3 118.8 Co3-C5-O3 94.4 C7-C6-Co3 2. 455 3.545 1.7 72 1.165 1.933 1.183 2. 446 3.558 1. 821 1.119 2. 022 1.157 140.3 61.9 177.4 106 .2 | 138.5 59.1 177.3 106.6 | 1850 21 00 Wavenumber cm-1 Figure C .2 Comparison between the theoretically... of analyzing the far-infrared region The collected spectra were obtain from monitoring the hydroformylation reaction of 3,3dimethy-l-butene was carried our using Rh4(CO) 12 as the catalyst precursor, see scheme G.1 O CH3 + CO + H2 CH3 CH3 H H Scheme G.1 Hydroformylation of 3,3-dimethyl-1-butene CH3 G.1 Experimental Setup The high pressure in- situ FTIR apparatus, described in chapter 3, Section 3 .2. 2,... with the experimental value of 116 Figure C.1 Optimized geometry of (μ4- 2- HC2H)Co4(CO)8(μ-CO )2 using DFT with PBE/DGDZVP 25 6 APPENDIX C Applying DFT to (μ4- 2- HC2H)Co4(CO)8(μ-CO )2 Table C.1 Comparison between predicted and experimental (obtained from McNeil and Scholer, 1977) bond distances (in Å) and angles (in deg) for (μ4- 2- HC2H)Co4(CO)8(μ-CO )2 DFT 1. 422 1.097 1.977 1.977 2. 527 C7-C6 C7-H2 Co1-C7... the autoclave Then, infrared spectra of the Rh4(CO)9(μ-CO)3/dissolved gas/n-hexane/3,3-dimethy-l-but-ene solution in the highpressure cell were recorded Hydroformylation reaction was initiated by introducing 2 MPa of H2 gas Then, spectra were recorded at 10 minute intervals in the range 400 -25 00 cm-1 The semi-batch experiment lasted 14-hours and circa 70 spectra were collected G.3 Far-infrared Region... Chew Numerical treatment of in- situ data for the pre-catalytic transformations of rhodium carbonyl species and implications AIChE Annual Meeting, Conference Proceedings, Austin, TX, United States, Nov 7- 12, 20 04 Allian, Ayman D.; Tjahjono, Martin; Garland, Marc Characterization of new rhodium complexes (μ 4- 2- hexyne)Rh4(CO)8(μ -CO )2: In situ FTIR investigation of the reaction of Rh4(CO)9(μ-CO)3 with... representative spectra of the far-infrared region, 400-700 cm-1, are shown in Figure G.1 Figure G.1 In- situ raw far-infrared spectra of the hydroformylation of 3,3-dimethyl-1-but-ene in the range 400-700 cm-1 G.4 Spectra Analysis The collected spectra were consolidated into one matrix A 73×1501 Then BTEM was used to reconstruct the pure component spectra present, see Figure G .2, following the same procedure... Meeting, Atlanta, GA, United States, March 26 -30, 20 06 Tjahjono, Martin; Allian, Ayman D.; Li, Chuanzhao; Garland, Marc Direct determination of the reaction volume of an organometallic reaction at very high dilution AIChE Annual Meeting, Conference Proceedings, Austin, TX, United States, Nov 7- 12, 20 04 Tjahjono, Martin; Allian, Ayman D.; Garland, Marc Determination of limiting partial molar volumes of. .. of isolatable and non-isolatable rhodium carbonyl clusters using mid-infrared vibrational spectra and density functional theory Abstracts of Papers, 23 1st ACS National Meeting, Atlanta, GA, United States, March 26 -30, 20 06 Allian, Ayman D.; Tjahjono, Martin; Garland, Marc Spectroscopic investigation of the butterfly cluster [(alkyne)Rh4(CO)10] and the kinetic of its formation Abstracts of Papers, 23 1st . wavenumbers (cm -1 ) for (μ 4 -η 2 -HC 2 H)Co 4 (CO) 8 (μ-CO) 2 Bridging Terminal CO stretches Expt 1879 20 00 20 23 20 40 20 43 20 53 20 93 DFT 1891 1999 20 09 20 29 20 32 2043 20 78 APPENDIX D RAMAN. distances (in Å) and angles (in deg) for (μ 4 -η 2 -HC 2 H)Co 4 (CO) 8 (μ-CO) 2 . Important distances DFT Exp Co1-Co2 2. 455 2. 446 C7-C6 1. 422 1.399 Co2-Co4 3.545 3.558 C7-H2 1.097 1.047 Co3-C 12 1.7 72. 1.7 72 1. 821 Co1-C7 1.977 1.9 82 C 12- O10 1.165 1.119 Co3-C6 1.977 1.9 82 Co3-C1 1.933 2. 022 Co1-Co3 2. 527 2. 559 C1-O5 1.183 1.157 Important angles DFT Exp Co3-C1-O5 140.3 138.5 C7-C6-H1 127 .5

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