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  1. Article ; Online: Molecular dynamics simulations and solid-state nuclear magnetic resonance spectroscopy measurements of C-H bond order parameters and effective correlation times in a POPC-GM3 bilayer.

    Fridolf, Simon / Hamid, Mona Koder / Svenningsson, Leo / Skepö, Marie / Sparr, Emma / Topgaard, Daniel

    Physical chemistry chemical physics : PCCP

    2022  Volume 24, Issue 41, Page(s) 25588–25601

    Abstract: ... restriction and dynamics of C-H bond segments can be measured using nuclear magnetic resonance ... to investigate how ganglioside GM3 affects the bilayer structure and dynamics of C-H bond segments. These two ... methods yield reorientational correlation functions, molecular profiles of C-H bond order parameters | ...

    Abstract Glycolipids such as gangliosides affect the properties of lipid membranes and in extension the interactions between membranes and other biomolecules like proteins. To better understand how the properties of individual lipid molecules can contribute to shape the functional aspects of a membrane, the spatial restriction and dynamics of C-H bond segments can be measured using nuclear magnetic resonance (NMR) spectroscopy. We combine solid-state NMR spectroscopy with all-atom molecular dynamics (MD) simulations to investigate how ganglioside GM3 affects the bilayer structure and dynamics of C-H bond segments. These two methods yield reorientational correlation functions, molecular profiles of C-H bond order parameters |
    MeSH term(s) Molecular Dynamics Simulation ; Lipid Bilayers/chemistry ; Magnetic Resonance Spectroscopy/methods ; Membranes ; Phosphatidylcholines/chemistry
    Chemical Substances Lipid Bilayers ; Phosphatidylcholines
    Language English
    Publishing date 2022-10-27
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/d2cp02860c
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Oxyfunctionalization of the Remote C-H Bonds of Aliphatic Amines by Decatungstate Photocatalysis.

    Schultz, Danielle M / Lévesque, François / DiRocco, Daniel A / Reibarkh, Mikhail / Ji, Yining / Joyce, Leo A / Dropinski, James F / Sheng, Huaming / Sherry, Benjamin D / Davies, Ian W

    Angewandte Chemie (International ed. in English)

    2017  Volume 56, Issue 48, Page(s) 15274–15278

    Abstract: ... either H ...

    Abstract Aliphatic amines, oxygenated at remote positions within the molecule, represent an important class of synthetic building blocks to which there are currently no direct means of access. Reported herein is an efficient and scalable solution that relies upon decatungstate photocatalysis under acidic conditions using either H
    Language English
    Publishing date 2017-10-26
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.201707537
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Hierarchy of relative bond dissociation enthalpies and their use to efficiently compute accurate absolute bond dissociation enthalpies for C-H, C-C, and C-F bonds.

    Chan, Bun / Radom, Leo

    The journal of physical chemistry. A

    2013  Volume 117, Issue 17, Page(s) 3666–3675

    Abstract: We have used the high-level W1X-2 and G4(MP2)-6X procedures to examine the performance of a variety of computationally less demanding quantum chemistry methods for the calculation of absolute bond dissociation enthalpies (BDEs) and a hierarchy of ... ...

    Abstract We have used the high-level W1X-2 and G4(MP2)-6X procedures to examine the performance of a variety of computationally less demanding quantum chemistry methods for the calculation of absolute bond dissociation enthalpies (BDEs) and a hierarchy of relative bond dissociation enthalpies. These include relative bond dissociation enthalpies (RBDEs), deviations from additivity of RBDEs (DARBDEs), and deviations from pairwise additivity of RBDEs (DPARBDEs). The absolute magnitudes of these quantities decrease in the order BDE > RBDE > DARBDE > DPARBDE, and overall, theoretical procedures are better able to describe these quantities in the same order. In general, the performance of the various types of procedures improves in the order pure DFT → hybrid DFT → double-hybrid DFT → composite procedures, as expected. Overall, we find M06-L to be the best-performing pure DFT procedure and M06-2X to be the best among the hybrid DFT methods. A promising observation is that even many pure and hybrid DFT procedures give DARBDE and DPARBDE values that are reasonably accurate. This can be exploited by using reference BDEs calculated at a higher-level of theory, in combination with DARBDE or DPARBDE values obtained at a lower level, to produce BDEs and RBDEs with an accuracy that is close to the directly calculated higher-level values. Strongly π-electron-withdrawing or π-electron-donating groups, however, sometimes represent challenges to these approximation methods when the substrate contains several of these substituents.
    Language English
    Publishing date 2013-05-02
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/jp401248r
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Mechanism, reactivity, and selectivity in Rh(III)-catalyzed phosphoryl-directed oxidative C-H activation/cyclization: a DFT study.

    Liu, Liu Leo / Wu, Yile / Wang, Tao / Gao, Xiang / Zhu, Jun / Zhao, Yufen

    The Journal of organic chemistry

    2014  Volume 79, Issue 11, Page(s) 5074–5081

    Abstract: ... directed oxidative C-H activation/cyclization to investigate the detailed mechanism, including four basic ... steps: C-H activation, alkyne insertion, reductive elimination, and catalyst recycling ... favorable in the C-H activation step in comparison with the Rh(III)-Ag2CO3 system, whereas the Rh(I)-Ag2CO3 ...

    Abstract Density functional theory calculations (DFT) have been performed on Rh(III)-catalyzed phosphoryl-directed oxidative C-H activation/cyclization to investigate the detailed mechanism, including four basic steps: C-H activation, alkyne insertion, reductive elimination, and catalyst recycling, each of which consists of different steps. Interestingly, the Rh(III)-AgOAc catalyst system was found to be more favorable in the C-H activation step in comparison with the Rh(III)-Ag2CO3 system, whereas the Rh(I)-Ag2CO3 catalyst system was more efficient for catalyst recycling. Importantly, our calculations suggest that the alkyne insertion process is a reversible step. Reductive elimination is the rate-determining step with an activation energy of 25.0 kcal/mol. In addition, the origin of the reactivity and selectivity difference between diarylacetylenes and dialkylacetylenes or electron-rich and electron-deficient diarylacetylenes was probed by means of comparative DFT calculations. The calculation results show that the electronic effects of alkynes play a key role in the reactivity and selectivity, in line with the experimental observations that diarylacetylenes and electron-rich diarylacetylenes are more reactive than dialkylacetylenes and electron-deficient diarylacetylenes, respectively. Our findings should be useful for further developments of transition-metal-catalyzed C-H activation reactions.
    MeSH term(s) Alkynes/chemistry ; Catalysis ; Cyclization ; Molecular Structure ; Oxidation-Reduction ; Quantum Theory ; Rhodium/chemistry
    Chemical Substances Alkynes ; Rhodium (DMK383DSAC)
    Language English
    Publishing date 2014-05-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/jo500616g
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Nickel-catalyzed decarboxylative C-P cross-coupling of alkenyl acids with P(O)H compounds.

    Wu, Yile / Liu, Liu Leo / Yan, Kaili / Xu, Pengxiang / Gao, Yuxing / Zhao, Yufen

    The Journal of organic chemistry

    2014  Volume 79, Issue 17, Page(s) 8118–8127

    Abstract: The first nickel-catalyzed decarboxylative C-P coupling of a wide range of alkenyl acids ... with various P(O)H compounds, especially for H-phosphonates, has been developed, affording a versatile and ...

    Abstract The first nickel-catalyzed decarboxylative C-P coupling of a wide range of alkenyl acids with various P(O)H compounds, especially for H-phosphonates, has been developed, affording a versatile and efficient tool for the preparation of valuable (E)-1-alkenylphosphonates, (E)-1-alkenylphosphinate oxides, and (E)-1-alkenylphosphine oxides with high stereoselectivity and broad substrate applicability. DFT calculation revealed that the phosphine ligand exhibits better catalytic performance than the nitrogen ligand in the reductive elimination step owing to the stronger nucleophilicity and larger size.
    MeSH term(s) Alkenes/chemistry ; Catalysis ; Ligands ; Molecular Structure ; Nickel/chemistry ; Nitrogen/chemistry ; Organophosphonates/chemistry ; Phosphines/chemistry ; Quantum Theory ; Stereoisomerism
    Chemical Substances Alkenes ; Ligands ; Organophosphonates ; Phosphines ; Nickel (7OV03QG267) ; phosphine (FW6947296I) ; Nitrogen (N762921K75)
    Language English
    Publishing date 2014-08-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/jo501321m
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Experimental and theoretical study on palladium-catalyzed C-P bond formation via direct coupling of triarylbismuths with P(O)-H compounds.

    Wang, Tao / Sang, Shuai / Liu, Liu Leo / Qiao, Hongwei / Gao, Yuxing / Zhao, Yufen

    The Journal of organic chemistry

    2013  Volume 79, Issue 2, Page(s) 608–617

    Abstract: ... H compounds has been developed that proceeds smoothly without exclusion of moisture or air and ... good to high yield. The coupling reaction is the first example of transition-metal-catalyzed C-P bond ... construction using triarylbismuth compounds as substrates. DFT calculations reveal that C-P bond formation is ...

    Abstract A novel and highly efficient Pd-catalyzed cross-coupling of triarylbismuths with a variety of P(O)-H compounds has been developed that proceeds smoothly without exclusion of moisture or air and provides a general and powerful tool for the preparation of various valuable arylphosphonates, arylphosphinates, and arylphosphine oxides, with high atom-economy, operational simplicity of the procedure, and good to high yield. The coupling reaction is the first example of transition-metal-catalyzed C-P bond construction using triarylbismuth compounds as substrates. DFT calculations reveal that C-P bond formation is the rate-determing step.
    MeSH term(s) Bismuth/chemistry ; Catalysis ; Molecular Structure ; Organometallic Compounds/chemistry ; Organophosphorus Compounds/chemical synthesis ; Organophosphorus Compounds/chemistry ; Palladium/chemistry ; Quantum Theory
    Chemical Substances Organometallic Compounds ; Organophosphorus Compounds ; Palladium (5TWQ1V240M) ; Bismuth (U015TT5I8H)
    Language English
    Publishing date 2013-12-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/jo402392t
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book: Reagents for direct functionalization of C-H bonds

    Fuchs, Philip L / Paquette, Leo A

    (Handbook of reagents for organic synthesis ; / ed.-in-chief: Leo A. Paquette ; 8)

    2007  

    Author's details ed. by Philip L. Fuchs
    Series title Handbook of reagents for organic synthesis
    / ed.-in-chief: Leo A. Paquette ; 8
    Language English
    Size VIII, 412 S., graph. Darst., 28 cm
    Publisher Wiley
    Publishing place Chichester
    Document type Book
    Note Literaturangaben
    ISBN 0470010223 ; 9780470010228
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  8. Article ; Online: High-resolution cavity ringdown spectroscopy of the jet-cooled propyl peroxy radical C(3)H(7)O(2).

    Just, Gabriel M P / Rupper, Patrick / Miller, Terry A / Meerts, W Leo

    Physical chemistry chemical physics : PCCP

    2010  Volume 12, Issue 18, Page(s) 4773–4782

    Abstract: ... G(1)T(2)) of the normal propyl peroxy radical, C(3)H(7)O(2), as well as the G conformer of the iso ...

    Abstract We have obtained high resolution, partially rotationally resolved, jet-cooled cavity ringdown spectra of the origin band of the A<--X electronic transition of two of the five conformers (G(1)G(2) and G(1)T(2)) of the normal propyl peroxy radical, C(3)H(7)O(2), as well as the G conformer of the iso-propyl peroxy radical isomer. This transition, located in the near infrared, was studied using a narrow band laser source (less than or approximately 250 MHz) and a supersonic slit-jet expansion coupled with an electric discharge allowing us to obtain rotational temperatures of about 15 K. All three spectra have been successfully fitted using an evolutionary algorithm approach with a Hamiltonian including rotational and spin-rotational terms. Excellent agreement with the experimental spectra was obtained by fitting seven molecular parameters in each of the ground and the first excited electronic states as well as the band origin of the electronic transition. These parameters are compared with the results from electronic structure calculations. This analysis confirms unambiguously the previous room-temperature conformer assignments that were based upon quantum chemistry calculations.
    Language English
    Publishing date 2010-05-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/b924323b
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Synthesis and reactivity of silyl ruthenium complexes: the importance of trans effects in C-H activation, Si-C bond formation, and dehydrogenative coupling of silanes.

    Dioumaev, Vladimir K / Procopio, Leo J / Carroll, Patrick J / Berry, Donald H

    Journal of the American Chemical Society

    2003  Volume 125, Issue 26, Page(s) 8043–8058

    Abstract: ... mechanisms, and aptitudes for PMe(3) dissociation and addition/elimination of H-H, Si-H, C-Si, and C-H bonds ... A series of octahedral ruthenium silyl hydride complexes, cis-(PMe(3))(4)Ru(SiR(3))H (SiR(3) = SiMe ... 3), 1a; SiMe(2)CH(2)SiMe(3), 1b; SiEt(3), 1c; SiMe(2)H, 1d), has been synthesized by the reaction ...

    Abstract A series of octahedral ruthenium silyl hydride complexes, cis-(PMe(3))(4)Ru(SiR(3))H (SiR(3) = SiMe(3), 1a; SiMe(2)CH(2)SiMe(3), 1b; SiEt(3), 1c; SiMe(2)H, 1d), has been synthesized by the reaction of hydrosilanes with (PMe(3))(3)Ru(eta(2)-CH(2)PMe(2))H (5), cis-(PMe(3))(4)RuMe(2) (6), or (PMe(3))(4)RuH(2) (9). Reaction with 6 proceeds via an intermediate product, cis-(PMe(3))(4)Ru(SiR(3))Me (SiR(3) = SiMe(3), 7a; SiMe(2)CH(2)SiMe(3), 7b). Alternatively, 1 and 7 have been synthesized via a fast hydrosilane exchange with another cis-(PMe(3))(4)Ru(SiR(3))H or cis-(PMe(3))(4)Ru(SiR(3))Me, which occurs at a rate approaching the NMR time scale. Compounds 1a, 1b, 1d, and 7a adopt octahedral geometries in solution and the solid state with mutually cis silyl and hydride (or silyl and methyl) ligands. The longest Ru-P distance within a complex is always trans to Si, reflecting the strong trans influence of silicon. The aptitude of phosphine dissociation in these complexes has been probed in reactions of 1a, 1c, and 7a with PMe(3)-d(9) and CO. The dissociation is regioselective in the position trans to a silyl ligand (trans effect of Si), and the rate approaches the NMR time scale. A slower secondary process introduces PMe(3)-d(9) and CO in the other octahedral positions, most likely via nondissociative isomerization. The trans effect and trans influence in 7a are so strong that an equilibrium concentration of dissociated phosphine is detectable (approximately 5%) in solution of pure 7a. Compounds 1a-c also react with dihydrogen via regioselective dissociation of phosphine from the site trans to Si, but the final product, fac-(PMe(3))(3)Ru(SiR(3))H(3) (SiR(3) = SiMe(3), 4a; SiMe(2)CH(2)SiMe(3), 4b; SiEt(3), 4c), features hydrides cis to Si. Alternatively, 4a-c have been synthesized by photolysis of (PMe(3))(4)RuH(2) in the presence of a hydrosilane or by exchange of fac-(PMe(3))(3)Ru(SiR(3))H(3) with another HSiR(3). The reverse manifold - HH elimination from 4a and trapping with PMe(3) or PMe(3)-d(9) - is also regioselective (1a-d(9)() is predominantly produced with PMe(3)-d(9) trans to Si), but is very unfavorable. At 70 degrees C, a slower but irreversible SiH elimination also occurs and furnishes (PMe(3))(4)RuH(2). The structure of 4a exhibits a tetrahedral P(3)Si environment around the metal with the three hydrides adjacent to silicon and capping the P(2)Si faces. Although strong Si...HRu interactions are not indicated in the structure or by IR, the HSi distances (2.13-2.23(5) A) suggest some degree of nonclassical SiH bonding in the H(3)SiR(3) fragment. Thermolysis of 1a in C(6)D(6) at 45-55 degrees C leads to an intermolecular CD activation of C(6)D(6). Extensive H/D exchange into the hydride, SiMe(3), and PMe(3) ligands is observed, followed by much slower formation of cis-(PMe(3))(4)Ru(D)(Ph-d(5)). In an even slower intramolecular CH activation process, (PMe(3))(3)Ru(eta(2)-CH(2)PMe(2))H (5) is also produced. The structure of intermediates, mechanisms, and aptitudes for PMe(3) dissociation and addition/elimination of H-H, Si-H, C-Si, and C-H bonds in these systems are discussed with a special emphasis on the trans effect and trans influence of silicon and ramifications for SiC coupling catalysis.
    Language English
    Publishing date 2003-07-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/ja035131p
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Structure and reactivity of bis(silyl) dihydride complexes (PMe(3))(3)Ru(SiR(3))(2)(H)(2): model compounds and real intermediates in a dehydrogenative C-Si bond forming reaction.

    Dioumaev, Vladimir K / Yoo, Bok R / Procopio, Leo J / Carroll, Patrick J / Berry, Donald H

    Journal of the American Chemical Society

    2003  Volume 125, Issue 29, Page(s) 8936–8948

    Abstract: A series of stable complexes, (PMe(3))(3)Ru(SiR(3))(2)(H)(2) ((SiR(3))(2) = (SiH(2)Ph)(2), 3a ... of hydridosilanes with (PMe(3))(3)Ru(SiMe(3))H(3) or (PMe(3))(4)Ru(SiMe(3))H. Compounds 3a and 3c adopt overall ... evidence for agostic Si-H interactions in 3a and 3b, the equatorial silyl group in 3c is in close contact ...

    Abstract A series of stable complexes, (PMe(3))(3)Ru(SiR(3))(2)(H)(2) ((SiR(3))(2) = (SiH(2)Ph)(2), 3a; (SiHPh(2))(2), 3b; (SiMe(2)CH(2)CH(2)SiMe(2)), 3c), has been synthesized by the reaction of hydridosilanes with (PMe(3))(3)Ru(SiMe(3))H(3) or (PMe(3))(4)Ru(SiMe(3))H. Compounds 3a and 3c adopt overall pentagonal bipyramidal geometries in solution and the solid state, with phosphine and silyl ligands defining trigonal bipyramids and ruthenium hydrides arranged in the equatorial plane. Compound 3a exhibits meridional phosphines, with both silyl ligands equatorial, whereas the constraints of the chelate in 3c result in both axial and equatorial silyl environments and facial phosphines. Although there is no evidence for agostic Si-H interactions in 3a and 3b, the equatorial silyl group in 3c is in close contact with one hydride (1.81(4) A) and is moderately close to the other hydride (2.15(3) A) in the solid state and solution (nu(Ru.H.Si) = 1740 cm(-)(1) and nu(RuH) = 1940 cm(-)(1)). The analogous bis(silyl) dihydride, (PMe(3))(3)Ru(SiMe(3))(2)(H)(2) (3d), is not stable at room temperature, but can be generated in situ at low temperature from the 16e(-) complex (PMe(3))(3)Ru(SiMe(3))H (1) and HSiMe(3). Complexes 3b and 3d have been characterized by multinuclear, variable temperature NMR and appear to be isostructural with 3a. All four complexes exhibit dynamic NMR spectra, but the slow exchange limit could not be observed for 3c. Treatment of 1 with HSiMe(3) at room temperature leads to formation of (PMe(3))(3)Ru(SiMe(2)CH(2)SiMe(3))H(3) (4b) via a CH functionalization process critical to catalytic dehydrocoupling of HSiMe(3) at higher temperatures. Closer inspection of this reaction between -110 and -10 degrees C by NMR reveals a plethora of silyl hydride phosphine complexes formed by ligand redistribution prior to CH activation. Above ca. 0 degrees C this mixture converts cleanly via silane dehydrogenation to the very stable tris(phosphine) trihydride carbosilyl complex 4b. The structure of 4b was determined crystallographically and exhibits a tetrahedral P(3)Si environment around the metal with the three hydrides adjacent to silicon and capping the P(2)Si faces. Although strong Si.HRu interactions are not indicated in the structure or by IR, the HSi distances (2.00(4) - 2.09(4) A) and average coupling constant (J(SiH) = 25 Hz) suggest some degree of nonclassical SiH bonding in the RuH(3)Si moiety. The least hindered complex, 3a, reacts with carbon monoxide principally via an H(2) elimination pathway to yield mer-(PMe(3))(3)(CO)Ru(SiH(2)Ph)(2), with SiH elimination as a minor process. However, only SiH elimination and formation of (PMe(3))(3)(CO)Ru(SiR(3))H is observed for 3b-d. The most hindered bis(silyl) complex, 3d, is extremely labile and even in the absence of CO undergoes SiH reductive elimination to generate the 16e(-) species 1 (DeltaH(SiH)(-)(elim) = 11.0 +/- 0.6 kcal x mol(-)(1) and DeltaS(SiH)(-)(elim) = 40 +/- 2 cal x mol(-)(1) x K(-)(1); Delta = 9.2 +/- 0.8 kcal x mol(-)(1) and Delta = 9 +/- 3 cal x mol(-)(1).K(-)(1)). The minimum barrier for the H(2) reductive elimination can be estimated, and is higher than that for silane elimination at temperatures above ca. -50 degrees C. The thermodynamic preferences for oxidative additions to 1 are dominated by entropy contributions and steric effects. Addition of H(2) is by far most favorable, whereas the relative aptitudes for intramolecular silyl CH activation and intermolecular SiH addition are strongly dependent on temperature (DeltaH(SiH)(-)(add) = -11.0 +/- 0.6 kcal x mol(-)(1) and DeltaS(SiH)(-)(add) = -40 +/- 2 cal.mol(-)(1) x K(-)(1); DeltaH(beta)(-CH)(-)(add) = -2.7 +/- 0.3 kcal x mol(-)(1) and DeltaS(beta)(-CH)(-)(add) = -6 +/- 1 cal x mol(-)(1) x K(-)(1)). Kinetic preferences for oxidative additions to 1 - intermolecular SiH and intramolecular CH - have been also quantified: Delta = -1.8 +/- 0.8 kcal x mol(-)(1) and Delta = -31 +/- 3 cal x mol(-)(1).K(-)(1); Delta = 16.4 +/- 0.6 kcal x mol(-)(1) and Delta = -13 +/- 6 cal x mol(-)(1).K(-)(1). The relative enthalpies of activation (-)(1) x K(-)(1)). Kinetic preferences for oxidative additions to 1 - intermolecular SiH and intramolecular CH - have been also quantified: Delta (H)SiH(add) = 1.8 +/- 0.8 kcal x mol(-)(1) and Delta S((SiH-add) =31+/- 3 cal x mol(-)(1) x K(-)(1); Delta S (SiH -add) = 16.4 +/- 0.6 kcal x mol(-)(1) and =Delta S (SiH -CH -add) =13+/- 6 cal x mol(-)(1) x K(-)(1). The relative enthalpies of activation are interpreted in terms of strong SiH sigma-complex formation - and much weaker CH coordination - in the transition state for oxidative addition.
    Language English
    Publishing date 2003-07-23
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/ja035916v
    Database MEDical Literature Analysis and Retrieval System OnLINE

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