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Aluminum and Palladium Complexes Containing Amido Phosphine Ligands: Synthesis, Structure, and ReactivityHuang, Mei-hui 26 August 2008 (has links)
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Synthesis of novel aminomethylphosphine complexesLastra Calvo, Nuria January 2015 (has links)
A new series of aminomethylphosphine ligands incorporating a PCN backbone and a pendant amine were synthesised using a phosphorus Mannich condensation reaction. Their coordination capabilities were investigated with late transition metal centres. Following a procedure well established within our research group, several phosphines were obtained using {P(CH2OH)4}Cl (THPC) in two steps. Firstly, THPC was reacted with various ortho and para anilines to give phosphonium salts P{CH2N(H)R}4Cl (R = C6H5, o-MeC6H4, o-i PrC6H4, o-t BuC6H4, o-FC6H4, o-CF3C6H4, o-{C(Me)=CH2}C6H4, p-MeC6H4, p-i PrC6H4, p-FC6H4 and p-EtC6H4). Secondly, these new salts were reacted with Et3N to obtain the cyclic RN(H)CH2P{(CH2)3(NR)2} phosphines (R = para-substituted anilines) or with KOt Bu to obtain acyclic P{CH2N(H)R}3 phosphines (R = ortho-substituted anilines) and cyclic P{CH2N(R)CH2}2P diphosphines (R = ortho-substituted anilines). Double condensation was observed in the 31P{1 H} NMR of cyclic phosphines RN(H)CH2P{(CH2)3(NR)2} to form {(CH2)3(NR)2}PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines. Some cyclic phosphines were investigated under a wide range of conditions with Ph2PCH2OH giving asymmetric Ph2PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines along with symmetric diphosphines counterparts and other phosphorus coproducts according to 31P{1 H} NMR and MS. A novel bicyclic OP{CH2N(R)CH2}3PO diphosphine (R = p-MeC6H4) was obtained as crystalline solid from the filtrate of the reaction between RN(H)CH2P{(CH2)3(NR)2} and Ph2PCH2OH and it was characterised by X-ray spectroscopy. Attempts to synthesise this diphosphine from P(CH2OH)3 and p-MeC6H4 were unsuccessful. The family of aminomethylphosphine ligands was extended by treating Ph2PCH2OH or CgPCH2OH (Cg = 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phosphaadamantane) with various primary amines to afford R(H)NCH2PR'2 (R' = Cg or Ph). Symmetric Ph2PCH2N(R)CH2Ph2 diphosphines were observed in the 31P{1 H} NMR spectra indicating that phosphines with Ph2P-moiety were more susceptible to undertake a second condensation. Novel asymmetric o-{Ph2PCH2C(H)(CH3)}C6H4N(H)CH2PPh2 diphosphine was synthesised by treatment of o-{C(Me)=CH2}C6H4NH2 with Ph2PH to afford o-{Ph2PCH2C(H)(CH3)}C6H4NH2 followed by condensation of the amino group with Ph2PCH2OH. Analogous o-{CgPCH2C(H)(CH3)}C6H4NH2 phosphine was also obtained. The coordination capabilities of selected compounds was studied with late transition metal precursor such as Pt(II), Pd(II) and Ru(II). Monophosphine compounds acted as Pmonodentate ligands to form square planar cis and trans MCl2L2 (M = Pt and Pd) complexes. However, whereas cyclic ligands RN(H)CH2P{(CH2)3(NR)2} afforded cisMCl2L2, acyclic ligands P{CH2N(H)R}3 afforded trans-MCl2L2 along with cis-PtCl2L2 in some cases. Those phosphines which conducted double condensation adopted a P,Pchelate mode to form a 6-membered M-P-C-N-C-P to afford cis-MCl2L (M = Pt and Pd). More interesting is the rarely observed P,P-bridging mode exhibited by P{CH2N(R)CH2}2P ligands to form homobimetallic cis-(PtCl2L)2 complexes and {RhCl2(η5 -Cp*)}2L complexes. These metal compounds were obtained and characterised by in situ NMR however their structures were further supported by simulated 31P{1 H} NMR and X-ray studies. Asymmetric Ph2PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines coordinated to Pt(II) in a P,P-chelate fashion affording a mixture of cis and trans bis(chelate) (PtL2)Cl2. Complex in trans geometry was isolated and the structure was further supported by X-ray crystallography. The coordination capabilities of the ligands were investigated with Ru(II) metal centre revealing 'piano-stool' structure of the type RuCl2(η6 -p-cymene)L where the monophosphines adopted a P-monodentate mode and {RuCl2(η6 -p-cymene)}2L where the diphosphines adopted a P,P-bridging mode. Preliminary studies with selected Ru complexes were carried out to investigate their potential catalytic activity to trap CO2 by its insertion into the Ru-Cl bond which suggested that the chloride needs to be substituted by a hydride prior the CO2 insertion. Compounds were characterised by spectroscopic techniques and the structure of some phosphines was further supported by X-ray crystallography.
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Unsymmetrical Complexes Containing the Linear Tetraphosphine Ligand DPPEPMNair, Padma, White, Colin P., Anderson, Gordon K., Rath, Nigam P. 15 January 2006 (has links)
The tetraphosphine DPPEPM reacts with [PtMe2(cod)] to produce [PtMe2(DPPEPM-PP)] (1) in near quantitative yield. On standing in solution, the free P atoms become oxidized to give [PtMe2(DPPEPM(O) 2-PP)] (1a), which has been characterized by X-ray crystallography. In contrast, reactions of DPPEPM with [MCl2(cod)] (M = Pd, Pt) yield ionic products of the form [M(DPPEPM-PP)2]MCl4 (3, 4). When a solution of the platinum complex was allowed to stand, crystals of [Pt(μ-Cl)(μ-DPPEPM)2]Cl3 (5) were obtained. In a third set of reactions, treatment of [PtClR(cod)] (R = Me, Ph) or [PdClMe(cod)] with DPPEPM gives species of the type [MR(DPPEPM-PPP)]Cl (6-8), in which one of the internal P atoms is uncoordinated. Reactions of [PtR2(DPPEPM-PP)] with [PtR2′(cod)] or [MCl2(cod)] (M = Pd, Pt), or of [PtR(DPPEPM-PPP)]Cl with [MCl2(cod)], lead to unsymmetrical bimetallic complexes. [PtMe2(μ-DPPEPM)PdCl2] (11) and [PtClPh(μ-DPPEPM)PdCl2] (14) have been characterized crystallographically. Trimetallic complexes of the form [{PtR 2(μ-DPPEPM)}2M][MCl4] (M = Pd, Pt, 15-17) are produced by reaction of [PtR2(DPPEPM-PP)] with [MCl 2(cod)].
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Sintese e heterogeneização de complexos de paladio : aplicação em reações de acoplamento C-C / Synthesis and heterogeneization of palladium complexes : application in C-C cross-coupling reactionsSato, Cintia Akemi 13 December 2007 (has links)
Orientador: Regina Buffon / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-11T02:19:50Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Neste trabalho, foram sintetizados complexos de paládio em que os ligantes fosforados estão ¿ancorados¿ em ciclofosfazenos. Estes complexos, em solução ou imobilizados em matrizes inorgânicas, foram testados nas reações de acoplamento de Suzuki (entre o ácido fenilborônico e o bromobenzeno, por exemplo), de Stille (entre o tributilvinilestanho e o bromotolueno) e de Heck (entre o estireno e o bromobenzeno). O resultado catalítico obtido com o catalisador sintetizado, em fase homogênea, na reação de Heck (TON = 3900, em 6 horas), foi muito bom, sendo superior a um catalisador análogo descrito na literatura. Na reação de Stille, o complexo, em fase homogênea, apresentou um ótimo resultado (TON = 4340, em 4 horas). Na reação de Suzuki, em fase homogênea, o TON obtido (123, em 24 horas) foi bom e comparável à literatura. Já em fase heterogênea, com o complexo encapsulado em matriz de sílica via processo solgel, os resultados obtidos, tanto na primeira reação quanto na primeira e segunda reciclagens, são superiores aos apresentados na literatura e apresentam o TON próximo ao obtido em fase homogênea, no mesmo tempo (92, 94 e 92 respectivamente), sem perda de desempenho. Estudos prospectivos para a imobilização do complexo em sílica foram realizados. O catalisador foi sintetizado com ligantes contendo grupos hidrolisáveis e ancorado em sílica. Este sistema foi testado nas reações de acoplamento de Stille e Suzuki, apresentando um bom desempenho nas duas reações (TON = 1400, em 4 horas, e 49, em 24 horas, respectivamente) sem constatação visual de lixiviação de paládio / Abstract: In this work, palladium complexes, in which phosphored ligands are ¿anchored¿ to cyclophosphazenes were synthesized. These complexes, in solution or immobilized in inorganic matrices, were tested in the Suzuki cross-coupling reaction (between phenylboronic acid and bromobenzene, for example), the Stille cross-coupling reaction (between tributylvinyltin and 3-bromotoluene) and the Heck reaction (between styrene and bromobenzene). The catalytic results obtained with the synthesized catalyst, in homogeneous phase, in the Heck reaction (TON = 3900, in 6 hours), was very good, better than those reported for a similar catalyst described in literature. In the Stille reaction, the complex, in homogeneous phase, presented an excellent result (TON = 4340, in 4 hours). In the Suzuki reaction, in homogeneous phase, the obtained TON (123, in 24 hours) was good and comparable to literature. In heterogeneous phase, with the complex encapsulated in silica matrix via the sol-gel process, the obtained results, in the first reaction as well as in the first and second recycling, are higher than those presented in literature and presented the TON close to that obtained in homogeneous phase, in the same reaction time (92, 94 and 92 respectively), without loss of performance. Prospective studies for the immobilization of the complex in silica were done. The catalyst was synthesized with ligands containing hydrolysable groups and anchored in silica. This system was tested in Stille and Suzuki cross-coupling reactions, showing a good performance in both reactions (TON = 1400, in 4 hours, and 49, in 24 hours, respectively) without visual evidence of palladium leaching / Mestrado / Quimica Inorganica / Mestre em Química
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Synthèse de la triphénylphosphine liée au polystyrène non réticulé et son utilisation lors de la réaction de Mitsunobu. Cyclopropanation catalytique énantiosélective d'alcènes utilisant le diazométhaneJanes, Marc K. January 2005 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.
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Metal-Catalysed HydroaminationShasha, Adelle January 2007 (has links)
Doctor of Philosophy(PhD), / This thesis describes the synthesis of terminal and internal amino and amidoalkynes and their hydroamination (cyclisation) catalysed by the complex (bis(N-methylimidazol-2-yl)methane)dicarbonylrhodium(I) tetraphenylborate (1). A series of analogous palladium complexes were also prepared and investigated for catalytic hydroamination. The scope of the rhodium(I) complex (1) for the intramolecular hydroamination of more complex amino and amidoalkyne substrates was investigated. This was made possible with the synthesis of aliphatic substrates, namely, 4 pentyn 1 amide (3) and 5 hexyn 1 amide (4) and a number of aromatic substrates, namely, 1, 4 diamino-2, 5 diethynylbenzene (5), 1, 4-diamino-2, 5 bis(phenylethynyl)benzene (6), 2, 3-diamino-1, 4-diethynylbenzene (7), 2, 3-diamino-1, 4-bis(phenylethynyl)benzene (8), 1, 5-bis(acetamido)-2, 4-diethynylbenzene (9), N-(acetyl)-2-ethynylbenzylamine (10) and N-(acetyl)-2-(phenylethynyl)benzylamine (11). The rhodium(I) complex (1) catalytically cyclised the aliphatic 4 pentyn 1 amide (3) regioselectively to the 6 membered ring, 3, 4 dihydro 2 pyridone (64) as the sole product. Attempts to cyclise 5 hexyn 1 amide (4) to produce either the 6 or 7 membered ring were unsuccessful. Compounds 5, 6, 7 and 8 were doubly cyclised to 1, 5 dihydro pyrrolo[2, 3 f]indole (71), 1, 5-dihydro-2, 6-diphenyl-pyrrolo[2, 3 f]indole (73), 1, 8-dihydro-pyrrolo[2, 3 g]indole (74) and 1, 8-dihydro-2, 7-diphenyl-pyrrolo[2, 3 g]indole (75) respectively. The aromatic amides with terminal acetylenes 9 and 10 cyclised to give 1, 7 diacetyl pyrrolo[3, 2 f]indole (76) and N (acetyl) 1, 2 dihydroisoquinoline (77) respectively. However, attempts to cyclise 11 were unsuccessful. Thus the rhodium(I) complex (1) successfully catalysed via hydroamination both terminal and internal acetylenic amine and amide substrates, to give pyridones, indoles and isoquinolines. Cationic and neutral palladium complexes incorporating the bidentate heterocyclic nitrogen donor ligand bis(N-methylimidazol-2-yl)methane (bim; 2) were synthesised: [Pd(bim)Cl2] (15), [Pd(bim)2][BF4]2 (17) [Pd(bim)(Cl)(CH3)] (14), [Pd(bim)(CH3)(NCCH3)][BF4] (16). All of the complexes were active as catalysts for the intramolecular hydroamination reaction, using the cyclisation of 4 pentyn 1 amine (21) to 2 methyl 1 pyrroline (22) as the model test reaction. Percentage conversions, turnover numbers and reaction profiles for each complex were compared to the rhodium(I) complex (1). These studies have shown that the catalytic activity was not significantly dependent on the bim donor ligand or the choice of metal. Substitution of the bim (2) ligand with the COD ligand and the use of methanol as the solvent did impact significantly on the efficiency of the hydroamination reactions.
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Studies Of Phosphorus-Functionalized Calix[4]arenes And Their Palladium ComplexesSarkar, Arindam 04 1900 (has links)
Calixarenes, particularly calix[4]arenes, continue to attract considerable attention in synthetic chemistry, notably as platforms for designing sophisticated molecular cages and claw-like ligands. Incorporation of phosphorus containing fragments into the calix[4]arene framework gives rise to new class of phosphorus ligands, called “calixphosphines”, a class of molecules that combine a catalytic center
(a transition metal) and a molecular receptor. This area of research has been growing rapidly in recent years. This thesis deals with the synthesis and a systematic study of conformational aspects of phosphorus functionalized calix[4]arene ligands and their palladium complexes. Several phosphorus functionalized calix[4]arene ligands and their (allyl) palladium complexes have been synthesized. The new compounds have been characterized by elemental analysis, NMR and IR spectroscopic data. The molecular structures of some representative compounds have been confirmed by single crystal X-ray diffraction studies.
Chapter 1 provides a brief overview of phosphorus functionalized calix[4]arenes and their transition metal chemistry with emphasis on aspects related to the theme of the present study. The scope and aim of the present investigation is outlined at the end of this chapter.
Chapter 2 presents the results obtained in the present investigation and a discussion of these results, especially spectroscopic and X-ray crystallographic data. The highlights of the present investigation and possible future directions are summarized at the end of this chapter.
Chapter 3 contains relevant details of the experimental procedures for the synthesis of calix[4]arene phosphite ligands and their palladium complexes. Spectroscopic and analytical data of these compounds are also given in this chapter. The details of single crystal diffraction studies are included at the end of this chapter. The references to the literature are compiled at the end of the thesis and are indicated in the text by appropriate numbers appearing as superscripts. The compounds synthesized in the present study are represented by bold arabic numerals. The abbreviations employed in this thesis are those generally used in Chemical Abstracts.
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Synthèse de la triphénylphosphine liée au polystyrène non réticulé et son utilisation lors de la réaction de Mitsunobu. Cyclopropanation catalytique énantiosélective d'alcènes utilisant le diazométhaneJanes, Marc K. January 2005 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal
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Towards the biaxial nematic phase via specific intermolecular interactionsOmnes, Laurent January 2001 (has links)
No description available.
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Metal-Catalysed HydroaminationShasha, Adelle January 2007 (has links)
Doctor of Philosophy(PhD), / This thesis describes the synthesis of terminal and internal amino and amidoalkynes and their hydroamination (cyclisation) catalysed by the complex (bis(N-methylimidazol-2-yl)methane)dicarbonylrhodium(I) tetraphenylborate (1). A series of analogous palladium complexes were also prepared and investigated for catalytic hydroamination. The scope of the rhodium(I) complex (1) for the intramolecular hydroamination of more complex amino and amidoalkyne substrates was investigated. This was made possible with the synthesis of aliphatic substrates, namely, 4 pentyn 1 amide (3) and 5 hexyn 1 amide (4) and a number of aromatic substrates, namely, 1, 4 diamino-2, 5 diethynylbenzene (5), 1, 4-diamino-2, 5 bis(phenylethynyl)benzene (6), 2, 3-diamino-1, 4-diethynylbenzene (7), 2, 3-diamino-1, 4-bis(phenylethynyl)benzene (8), 1, 5-bis(acetamido)-2, 4-diethynylbenzene (9), N-(acetyl)-2-ethynylbenzylamine (10) and N-(acetyl)-2-(phenylethynyl)benzylamine (11). The rhodium(I) complex (1) catalytically cyclised the aliphatic 4 pentyn 1 amide (3) regioselectively to the 6 membered ring, 3, 4 dihydro 2 pyridone (64) as the sole product. Attempts to cyclise 5 hexyn 1 amide (4) to produce either the 6 or 7 membered ring were unsuccessful. Compounds 5, 6, 7 and 8 were doubly cyclised to 1, 5 dihydro pyrrolo[2, 3 f]indole (71), 1, 5-dihydro-2, 6-diphenyl-pyrrolo[2, 3 f]indole (73), 1, 8-dihydro-pyrrolo[2, 3 g]indole (74) and 1, 8-dihydro-2, 7-diphenyl-pyrrolo[2, 3 g]indole (75) respectively. The aromatic amides with terminal acetylenes 9 and 10 cyclised to give 1, 7 diacetyl pyrrolo[3, 2 f]indole (76) and N (acetyl) 1, 2 dihydroisoquinoline (77) respectively. However, attempts to cyclise 11 were unsuccessful. Thus the rhodium(I) complex (1) successfully catalysed via hydroamination both terminal and internal acetylenic amine and amide substrates, to give pyridones, indoles and isoquinolines. Cationic and neutral palladium complexes incorporating the bidentate heterocyclic nitrogen donor ligand bis(N-methylimidazol-2-yl)methane (bim; 2) were synthesised: [Pd(bim)Cl2] (15), [Pd(bim)2][BF4]2 (17) [Pd(bim)(Cl)(CH3)] (14), [Pd(bim)(CH3)(NCCH3)][BF4] (16). All of the complexes were active as catalysts for the intramolecular hydroamination reaction, using the cyclisation of 4 pentyn 1 amine (21) to 2 methyl 1 pyrroline (22) as the model test reaction. Percentage conversions, turnover numbers and reaction profiles for each complex were compared to the rhodium(I) complex (1). These studies have shown that the catalytic activity was not significantly dependent on the bim donor ligand or the choice of metal. Substitution of the bim (2) ligand with the COD ligand and the use of methanol as the solvent did impact significantly on the efficiency of the hydroamination reactions.
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