Download or read book Syntheses Structures and Reactivity Studies of Transition metal Silyl and Silene Complexes written by Brian K. Campion and published by . This book was released on 1990 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Syntheses and Reactivity Studies of Transition Metal Complexes Featuring Metal Main Group Multiple Bonds written by Meg E. Fasulo and published by . This book was released on 2012 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ruthenium triflate complex Cp*(PiPr3)RuOTf (1) was generated from the reaction of Cp*(PiPr3)RuCl with Me3SiOTf in dibutyl ether. Complex 1 reacted with primary and secondary silanes to produce a family of Ru(IV) silyl dihydride complexes of the type Cp*(PiPr3)Ru(H)2(SiRR'OTf) (3 - 12). Structural analyses of complexes 8 (R = R' = Ph) and 12 (R = R' = fluorenyl) revealed the presence of a tetrahedral silicon center and a four-legged piano stool geometry about ruthenium. Anion abstraction from Cp*(PiPr3)Ru(H)2(SiHROTf) by [Et3Si*toluene][B(C6F5)4] afforded hydrogen-substituted cationic ruthenium silylene complexes [Cp*(PiPr3)Ru(H)2(=SiHR)][B(C6F5)4] (R = Mes (13), R = Si(SiMe3) (14)) that display a significant Ru - H ... Si interaction, as indicated by relatively large 2JSiH coupling constants (2JSiH = 58.2 Hz (13), 2JSiH = 37.1 Hz (14)). The syntheses of secondary silylene complexes [Cp*(PiPr3)Ru(H)2(=SiRR')][B(C6F5)4] (R = R' = Ph (15); R = Ph, R' = Me (16), R = R' = fluorenyl (17)) were also achieved by anion abstraction with [Et3Si*toluene][B(C6F5)4]. Complexes 15 - 17 do not display strong Ru - H ... Si secondary interactions, as indicated by very small 2JSiH coupling constant values. The cationic ruthenium silylene complex [Cp*(PiPr3)Ru(H)2(SiHMes)] [CB11H6Br6], a catalyst for olefin hydrosilations with primary silanes, was isolated and characterized by X-ray crystallography. Relatively strong interactions between the silylene Si atom and Ru-H hydride ligands appear to reflect a highly electrophilic silicon center. Kinetic and mechanistic studies on hydrosilations with this catalyst reveal a fast, initial addition of the Si-H bond of the silylene complex to the olefin. Subsequent migration of a hydride ligand to silicon produces a 16-electron intermediate, which can be trapped by olefin, resulting in inhibition of catalysis, or intercepted by the silane substrate. The latter reaction pathway, involving oxidative addition of the Si-H bond and a somewhat concomitant loss of product, is the rate-determining step in the catalytic cycle. Reactions of the cationic ruthenium silylene complexes [Cp*(PiPr3)Ru(H)2(=SiRR')][B(C6F5)4] (R = Mes, R' = H, 1; R = R' =Ph, 2) with alkenes, alkynes, ketones, and Lewis bases were explored. Addition of 1-hexene, 3,3-dimethylbut-1-ene, styrene, and cyclopentene to 1 afforded the disubstituted silylene products [Cp*(PiPr3)Ru(H)2(=SiMesR)][B(C6F5)4] (R = Hex, 3; R = CH2CH2tBu, 4; R = CH2CH2Ph, 5; R = C5H9, 6). Analogous reactions with 2-butyne and 3,3-dimethylbut-1-yne yielded the vinyl-substituted silylene complexes [Cp*(PiPr3)Ru(H)2(=Si(CR=CHR')Mes)][B(C6F)4] (R = R' = Me, 7; R = H, R' = tBu, 8). Complex 1 undergoes reactions with ketones to give the heteroatom-substituted silylene complexes [Cp*(PiPr3)Ru(H)2(=Si(OCHPhR)Mes)][B(C6F)4] (R = Ph, 9; R = Me, 10). Interestingly, complexes 3 - 8 display a weak interaction between the hydride ligands and the silicon center, while 9 and 10 exhibit a relatively large interaction (as determined by 2JSiH values). The reaction of isocyanates with 1 resulted in the silyl complexes [Cp*(PiPr3)Ru(H)2(Si(Mes)[n2-O(CH)(NC6H4R)][B(C6F5)4] (R = H, 11; R = CF3, 12), and an intermediate in this transformation is observed. Complex 2 was subjected to various Lewis bases to yield the base-stabilized silylene complexes [Cp*(PiPr3)Ru(H)2(SiPh2*L)][B(C6F)4] (L = DMAP, 13; L = Ph2CO, 14; L = PhCONH2, 15; L = NHMePh, 16, L = tBuSONH2, 18) and the reaction of 1 with NHMePh gave [Cp*(PiPr3)Ru(H)2(SiHMes*NHMePh)][B(C6F)4]. The cationic germylene complex [Cp*(PiPr3)Ru(H)2(=GeMes2)][OTf] (1) was synthesized from the reaction of Cp*(PiPr3)RuOTf with H2GeMes2, and addition of DMAP to 1 yielded the neutral germylene complex [Cp*(PiPr3)Ru(H)(=GeMes2) (2). The reaction of H3GeTrip and Cp*(PiPr3)RuCl gave the germyl complex Cp*(PiPr3)Ru(H)2(GeHTripCl) (3), which undergoes a reaction with Li(Et2O)2[B(C6F5)4] to afford the cationic H-substituted germylene complex [Cp*(PiPr3)Ru(H)2(=GeHTrip)][B(C6F5)4] (4). Addition of 1-hexene, 3,3-dimethylbut-1-ene, styrene, and allyl chloride to 4 afforded the disubstituted germylene products [Cp*(PiPr3)Ru(H)2(=GeTripR)][B(C6F5)4] (R = Hex, 5; R = CH2CH2Ph, 6; R = CH2CH2tBu, 7; R = CH2CH2CH2Cl, 8). Analogous reactions with 2-butyne and 3,3-dimethylbut-1-yne yielded the vinyl-substituted germylene complexes [Cp*(PiPr3)Ru(H)2(=Ge(CR=CHR')Trip)][B(C6F)4] (R = H, R' = tBu, 9; R = R' = Me, 10). New di(phosphine)-supported rhodium and iridium silyl complexes were synthesized. Reactions of the di(t-butylphosphino)ethane complex (dtbpe)Rh(CH2Ph) with Ph2SiH2 and Et2SiH2 resulted in isolation of (dtbpe)Rh(H)2(SiBnPh2) (1, Bn = CH2Ph) and (dtbpe)Rh(H)2(SiBnEt2) (2), respectively. Both 1 and 2 display strong interactions between the rhodium hydride ligands and the silyl ligand, as indicated by large 2JSiH values (44.4 and 52.1 Hz). The reaction of (dtbpm)Rh(CH2Ph) (dtbpm = di(t-butylphosphino)methane) with Mes2SiH2 gave the pseudo-three-coordinate Rh complex (dtbpm)Rh(SiHMes2) (3), which is stabilized in the solid state by agostic interactions between the rhodium center and two C - H bonds of a methyl substituent of a mesityl group. The analogous germanium compound (dtbpm)Rh(GeHMes2) (4) is also accessible. Complex 3 readily undergoes reactions with diphenylacetylene, phenylacetylene, and 2-butyne to give the silaallyl complexes (dtbpm)Rh[Si(CPh=CHPh)Mes2] (5), (dtbpm)Rh[Si(CH=CHPh)Mes2] (7), and (dtbpm)Rh(Si(CMe=CHMe)Mes2) (8) via net insertions into the Si - H bond. The germaallyl complexes (dtbpm)Rh[Ge(CPh=CHPh)Mes2] (6) and (dtbpm)Rh[Ge(CMe=CHMe)Mes2] (9) were synthesized under identical conditions starting from 4. The reaction of (dtbpm)Rh(CH2Ph) with 1 equiv of TripPhSiH2 yielded (dtbpm)Rh(H)2[5,7-diisopropyl-3-methyl-1-phenyl-2,3-dihydro-1H-silaindenyl-kSi] (11), and catalytic investigations indicate that both (dtbpm)Rh(CH2Ph) and 11 are competent catalysts for the conversion of TripPhSiH2 to 5,7-diisopropyl-3-methyl-1-phenyl-2,3-dihydro-1H-silaindole. A dtbpm-supported Ir complex, [(dtbpm)IrCl]€2, was used to access the dinuclear bridging silylene complexes [(dtbpm)IrH](SiPh2)(Cl)2[(dtbpm)IrH] (12) and [(dtbpm)IrH](SiMesCl)( -Cl)(H)[(dtbpm)IrH] (13). The reaction of [(dtbpm)IrCl]2 with a sterically bulky primary silane, (dmp)SiH3 (dmp = 2,6-dimesitylphenyl), allowed isolation of the mononuclear complex (dtbpm)Ir(H)4(10-chloro-1-mesityl-5,7-dimethyl-9,10-dihydrosilaphenanthrene-Si) (14), in which the dmp substituent has undergone C-H activation. The dichloride complex Cp*(Am)WCl2 (1, Am = [(iPrN)2CMe]- ) reacted with the primary silanes PhSiH3, (p-tolyl)SiH3, (3,5-xylyl)SiH3, and (C6F5)SiH3 to produce the W(VI) (silyl)trihydrides Cp*(Am)W(H)3(SiHPhCl) (2), Cp*(Am)W(H)3(SiHTolylCl) (3), Cp*(Am)W(H)3(SiHXylylCl) (4), and Cp*(Am)W(H)3[SiH(C6F5)Cl] (5). In an analogous manner, 1 reacted with PhSiH2Cl to give Cp*(Am)W(H)3(SiPhCl2) (6). Complex 6 can alternatively be quantitatively produced from the reaction of 2 with Ph3CCl. NMR spectroscopic studies and X-ray crystallography reveal an interligand H ... Si interaction between one W - H and the chlorosilyl group, which is further supported by DFT calculations. Complexes of Ru(II) containing the pincer ligand [-N(2-PPh2-4-Me-C6H3)2] (PNPPh) were prepared. The complex (PNPPhH)RuCl2 (1) was treated with 2 equiv AgOTf to produce the triflate complex (PNPPhH)Ru(OTf)2 (2). Complex 1 was also treated with an excess of NaBH4 to give a bimetallic complex [(PNPPh)RuH3]2 (3). A number of methods, including X-ray crystallography, NMR spectroscopy, and computational studies, were used to probe the structure of 3. Addition of Lewis bases to 3 resulted in octahedral complexes containing a hydride ligand trans to a dihydrogen ligand.
Download or read book Transition metal Silyl Complexes with Novel Coordination Environments written by Richard Hamilton Heyn and published by . This book was released on 1992 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetically Controlled Stepwise Syntheses of a Heterometallic Complex and a Tetrahedral Chiral at Metal Complex written by Kenichi Endo and published by Springer Nature. This book was released on 2021-04-01 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes novel synthetic methodologies for two kinds of structurally elaborate metal complexes: a heterometallic complex and a tetrahedral chiral-at-metal complex. The book provides the tools and inspiration to chemists for development of metal complexes with wide structural diversity than had previously been possible. For each of the two topics, existing synthetic methods for similar compounds are discussed first, and then new strategies are presented, followed by the demonstration of the synthesis of novel compounds supported by experimental results. Both of the final products in this research, a Co–Ni heterometallic complex covered in the first topic and a tetrahedral chiral-at-metal complex in the second one are difficult to obtain by using common synthetic methods for thermodynamic reasons. This research achieved highly selective syntheses of these compounds using newly designed strategies that enable precise kinetic control. Such an approach will be useful for synthesizing other new metal complexes. Since the last century, organic chemistry has flourished with the development of a variety of synthetic techniques that make precise kinetic control possible. Coordination chemistry of 3d or main-group transition metals has been mainly based on simple one-step reactions that yield only thermodynamic products. The publication of this book helps pave the way to kinetically controlled precise syntheses of various metal complexes.
Download or read book Synthesis Structure and Reactivity of Silyl Derivatives of Tantalum and Niobium written by John Arnold and published by . This book was released on 1986 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition Metals in Supramolecular Chemistry written by L. Fabbrizzi and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the pioneering publications on coordination chemistry by Lehn and Pedersen in the late 1960s, coupled with the more orthodox interest from the transition metal chemists on template reactions (Busch, 1964), the field of supramolecular chemistry has grown at an astonishing rate. The use of transition metals as essential constituents of multi-component assemblies has been especially sharp in recent years, since the metals are prone to quick and reversible redox changes, and there is a wide variety of metal--ligand interactions. Such properties make supramolecular complexes of transition metal ions suitable candidates for exploration as light--energy converters and signal processors. Transition Metals in Supramolecular Chemistry focuses on the following main topics: (1) metal controlled organization of novel molecular assemblies and shapes; (2) design of molecular switches and devices operating through metal centres; (3) supramolecular catalysts that mimic metalloenzymes; (4) metal-containing sensory reagents and supramolecular recognition; and (5) molecular materials that display powerful electronic, optoelectronic and magnetic properties.
Download or read book Synthesis Structure and Catalysis of Transition Metal Silyl and Germyl Complexes written by Christine Maya Popoff and published by . This book was released on 1995 with total page 1314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Structure and Reactivity of Silicon and Germanium Isocyanide Complexes of Transition Metals written by David B. Shaw and published by . This book was released on 1975 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Syntheses and Structural Studies of Transition Metal Complexes written by Anthony Vinciguerra and published by . This book was released on 1962 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition Metal Complexes with P N ligands and Silylenes written by Eva Neumann and published by . This book was released on 2006 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Characterization and Reactivity of Transition Metal Complexes Containing Multi donor Ligands written by John C. Linehan and published by . This book was released on 1986 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition Metals in the Synthesis of Complex Organic Molecules written by Louis S. Hegedus and published by University Science Books. This book was released on 1994 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: A text for use in a one-semester course for upper-level students familiar with basic organic chemistry, or as a survey course for practicing organic chemists. Chapters 1 and 2 present a brief overview of the formalisms and mechanisms required to understand the processes discussed in chapters 3-10, which deal with the application of transition metal organometallic chemistry to organic synthesis with specific attention to applications with complex molecules. Updates and expands chapters 13-20 of Principles and Applications of Organotransition Metal Chemistry, 2nd ed. (1987). Published by University Science Books, 20 Edgehill Rd., Mill Valley, CA 94941. Annotation copyright by Book News, Inc., Portland, OR
Download or read book On Being Well coordinated written by Fred Basolo and published by World Scientific. This book was released on 2003 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: This invaluable book distils the research accomplishments of Professor Fred Basolo during the five decades when he served as a world leader in the modern renaissance of inorganic chemistry. Its primary focus is on the very important area of chemistry known as coordination chemistry.Most of the elements in the periodic table are metals, and most of the chemistry of metals involves coordination chemistry. This is the case in the currently significant areas of research, including organometallic homogenous catalysis, biological reactions of metalloproteins, and even the solid state extended structures of new materials. In these systems, the metals are of primary importance because they are the sites of ligand substitution or redox reactions. In the solid materials, the coordination number of the metal and its stereochemistry are of major importance.Some fifty years of research on transition metal complexes carried out in the laboratory of Professor Basolo at Northwestern University is recorded here as selected scientific publications. The book is divided into three different major research areas, each dealing with some aspect of coordination chemistry. In each case, introductory remarks are presented which indicate what prompted the research projects and what the major accomplishments were. Although the research was of the academic, curiosity-driven type, some aspects have proven to be useful to others involved in projects that were much more applied in nature.
Download or read book Synthesis and Study of Transition Metal Siylene Complexes and Development of Iridium Chemistry Featuring the PhB CH2PPH2 3 Ligand written by Jay Dell Feldman and published by . This book was released on 2002 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Characterization of Transition Metal Silyl Complexes and Phthalocyanine and Phthalocyanine like Compounds written by Vance Owen Kennedy and published by . This book was released on 1993 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Characterization and Computational Studies of Unsaturated Transition Metal Complexes written by Lori Anne Watson and published by . This book was released on 2004 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
