Showing papers by "Paul von Ragué Schleyer published in 1984"
TL;DR: In this article, the authors composes MCH 2 X avec M=Li ou Na et X=CH 3, NH 2, OH, F, SiH 3, PH 2, SH ou Cl, avec corrections de correlation electronique.
Abstract: Calculs ab initio sur les composes MCH 2 X avec M=Li ou Na et X=CH 3 , NH 2 , OH, F, SiH 3 , PH 2 , SH ou Cl, avec corrections de correlation electronique. Comparaison avec especes anioniques correspondantes
262 citations
TL;DR: In this article, the cyclopropane isopropyle of a cycloprocessor is compared with the isoprophylique of an isoprogene.
Abstract: Calculs MO ab initio (4-31 G) sur les cyclopropanes C 3 H 5 X et les composes isopropyliques C 3 H 7 X avec X=Li, BeH, BH 2 , CH 3 , NH 2 , OH, F: le groupe cyclopropyle est plus electronegatif que le groupe isopropyle. Discussion en termes d'interactions d'orbitales
108 citations
TL;DR: In this article, it was shown that les molecules ONa 3 and ONa 4 sont stables avec des liaisons Na-O un peu plus longues que dans Na 2 O et NaOH and that les 9eme and 10eme electrons of ces molecules hypervalentes interviennent dans la liaison metal-metal plutot.
Abstract: Calculs MO ab initio montrant que les molecules ONa 3 et ONa 4 sont stables avec des liaisons Na-O un peu plus longues que dans Na 2 O et NaOH et que les 9eme et 10eme electrons de ces molecules hypervalentes interviennent dans la liaison metal-metal plutot que dans la liaison metal-O
49 citations
40 citations
31 citations
TL;DR: In this article, the reactions of alkyl-and dialkylbenzenes avec des melanges 1:1 de n-butyl-Li and de t-pentanolate de K for radicaux anioniques are studied.
Abstract: Etude des reactions des alkyl- et dialkylbenzenes avec des melanges 1:1 de n-butyl-Li et de t-pentanolate de K pour donner des anions toluenures. Metallation. Spectres RPE de radicaux anioniques. Calculs MNDO
31 citations
TL;DR: In this paper, a MO ab initio sur les complexes entre le formaldehyde and les cations Li +, BeH +, BH 2 +, CH 3 OCH 2 + (angle COC de 128,0°), SiH 3 O CH 2+ (angle SiOC de 148,9°) and BH2 OCH2+ plan (angle BOC de 131,4°) is computed.
Abstract: Calculs MO ab initio sur les complexes entre le formaldehyde et les cations Li + , BeH + , BH 2 + , CH 3 + , Na + , MgH + , AlH 2 + , SiH 3 + ; les geometries les plus stables correspondant a un motif lineaire m−O−C sauf pour CH 3 OCH 2 + (angle COC de 128,0°), SiH 3 OCH 2 + (angle SiOC de 148,9°) et BH 2 OCH 2 + plan (angle BOC de 131,4°)
28 citations
TL;DR: In this article, the MP2/6-311G(2d, 2p) level indicates the ground-state Li*H2 complex to be only a very weakly bound (≈13 kcal/mol) van der Waals species.
27 citations
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20 citations
TL;DR: In this paper, the authors present a tripartite liaison du carbone central (1,388 A) that is considerably more courte than les 2 autres ( 1,433 A and 1,46 A) in the groupe P1.
Abstract: Cristallisation dans le groupe P1. Affinement jusqu'a R=0,152. Une des trois liaisons du carbone central est considerablement plus courte (1,388 A) que les 2 autres (1,433 A et 1,46 A). Cette assymetrie plus importante que celle pouvant etre causee par la presence des 2 coordinats TMEDA, est due aux interactions avec les 2 Li
TL;DR: A comparison of experimentally derived Qmin data for the process m+→m2+ with the computed vertical ionization energies, I.E.v suggests that whereas electron removal from CH2XH+· results directly in the formation of the corresponding dications, i.e. CH 2XH2+, charge stripping from CH3Z+˙ does not lead to stable CH3X2+ species, but instead rearrangement (perhaps from a Rydberg state of CH3xH2+ ions) is likely to take place to give CH
Abstract: Charge stripping from aither Ch2XH+˙ or CH3X+˙ cation radicals (X = F, Cl, Br, I, OH, SH, or NH2) results in the formation of ovservable dications; a comparison of experimentally derived Qmin data for the process m+→m2+ with the computed vertical ionization energies, I.E.v suggests that whereas electron removal from CH2XH+· results directly in the formation of the corresponding dications, i.e. CH2XH2+, charge stripping from CH3Z+˙ does not lead to stable CH3X2+ species, but instead rearrangement (perhaps from a Rydberg state of CH3X+˙) is likely to take place to give CH2XH2+ ions.
TL;DR: Methane, when used to activated supported nickel catalysts, react at ca. 300 °C with benzene, cyclopentene, methylenecyclopentane, and simple alkenes to give modest but definite amounts of higher hydrocarbons.
Abstract: Methane, when used to activated supported nickel catalysts, react at ca. 300 °C with benzene, cyclopentene, methylenecyclopentane, and simple alkenes to give modest but definite amounts of higher hydrocarbons.
TL;DR: In this article, the lithium atoms in the title compound were shown by X-ray analysis to prefer quite different locations, in contrast to the symmetrical double bridging exhibited by other 1,4-dilithium compounds, but in agreement with model MNDO calculations.
Abstract: The lithium atoms in the title compound are shown by X-ray analysis to prefer quite different locations, in contrast to the symmetrical double bridging exhibited by other 1,4-dilithium compounds, but in agreement with model MNDO calculations; furthermore, the (E,E) conformation of the two phenyl groups differs from the (E,Z) conformation reported in methyltetrahydrofuran solution.
TL;DR: In this article, the authors show that symmetric double bridging, commonly exhibited by 1,4-dilithium compounds e.g. in (1) and (2), is not favored in (4) and(5) since charge deloclization in the dianion, hybridization, and orbital orientation effects are more important than quadrupole-like electrostatic interactions.
Abstract: Symmetrical (C2v) double bridging, commonly exhibited by 1,4-dilithium compounds e.g. in (1) and (2), is not favoured in (4) and (5) since charge deloclization in the dianion, hybridization, and orbital orientation effects are more important than quadrupole-like electrostatic interactions (3).
TL;DR: The ESR spectrum of the cycloheptatrienyl radical dianion, which is in equilibrium with the corresponding trianion generated by the reaction of cyclohexene with a 1/1 n-butyllithium/potassium tamyloxide mixture, is characteristic of the potassium rather than the lithium salt.
TL;DR: In this paper, the lithium ion dianions were synthesized and investigated by 1H and 13C n.m.n.r. spectroscopy, showing that the dibenzylidenemethylenemethane dianion is a mixture of two isomers, exo,endo and a symmetrical form, probably exo-exo.
Abstract: The lithium salts of the two title dianions have been synthesised and investigated by 1H and 13C n.m.r. spectroscopy. Whereas the dibenzylidenemethylenemethane dianion salt exists exclusively in the exo,exo conformation, its oxa-analogue is a mixture of two isomers, exo,endo and a symmetrical form, probably exo,exo. The benzyl α,β-CC bond rotation barrier in the ketone dianion salt in THF is 10.8 ± 0.5 kcal mol–1. The phenyl rotation barrier in the hydrocarbon dianion salt is similar (10.9 kcal mol–1), as are the charge distributions in the benzylidene groups of the two dianions.
TL;DR: La forme chirale avec conjugaison en forme de Y est la plus stable des 5 structures calculees as discussed by the authors, i.e., it is the most stable structure calcule.
Abstract: La forme chirale avec conjugaison en forme de Y est la plus stable des 5 structures calculees
TL;DR: The bicyclo[3.3.0] octadienediyl dianion (3) ring opens to give the cyclo-octatetraene dianions (4), the reverse of the behaviour shown by the corresponding dication.
Abstract: The bicyclo[3.3.0]octadienediyl dianion (3) ring opens to give the cyclo-octatetraene dianion (4), the reverse of the behaviour shown by the corresponding dication.