Showing papers on "Norbornadiene published in 1984"
TL;DR: Racemic 2, 2'-bis(diphenylphosphino)-l, 1'-binaphthyl has been synthesized from 2 2, 2'-dihydroxy-l, l'-biosphine in two steps and resolved into optically pure (R)-(+) and (S) (-) enantiomers by the use of (+)-di-μ-chlorobis[(S)-N,N-dimethyl-α-phenylethylamine-2C,N]dipalladium.
230 citations
TL;DR: In this paper, the authors present des catalyseurs actifs de la migration d'hydrogene dans les allylamines secondaires et tertiaires pour donner les (E)-enamines et imines correspondants.
Abstract: Utilisation de complexes de Rh(I) du type [Rh(diphosphine) (diene)]ClO 4 et [Rh(diphosphine)(S) 4 ]ClO 4 (diphosphine: diphosphine tertiaire chelatant-cis; diene=cyclooctadiene ou norbornadiene; S=solvant). Ces composes sont des catalyseurs actifs de la migration d'hydrogene dans les allylamines secondaires et tertiaires pour donner les (E)-enamines et imines correspondants
216 citations
171 citations
TL;DR: In this paper, a paramagnetic ruthenium(III) complex is prepared by the reaction of RuCl3·H2O with C5Me5H in refluxing ethanol.
Abstract: Paramagnetic ruthenium(III) complex, [(C5Me5)RuCl2]n, is prepared by the reaction of RuCl3·H2O with C5Me5H in refluxing ethanol. Treatment of [Cp*RuCl2]n (Cp* = C5Me5) with cyclic dienes or α,ω-bis(diphenylphosphino)alkanes gives diamagnetic Ru(II) complexes, Cp*RuCl(diene) or Cp*RuCl(dipos), respectively. Cationic diene complex of ruthenium is formed by the reaction of Cp*RuCl(2,5-norbornadiene) with AgBF4.
157 citations
122 citations
TL;DR: The Ziegler catalyst TiCl 4 -Et 2 AlCl and the arenetitanium(II) complex (η6-C 6 H 6 )Ti(II)(AlCl 4 ) 2 induce [6 + 2]cycloaddition reactions of cycloheptatriene with dienes and acetylenes.
54 citations
TL;DR: In this article, WBr 2 (CO) 2 (C 7 H 8 ) cristallise dans le systeme monoclinique, groupe P2 1 /n and le compose WBr2 (CO 2 (PPh 3 ) 2 dans the systeme triclinique.
Abstract: Le compose WBr 2 (CO) 2 (C 7 H 8 ) cristallise dans le systeme monoclinique, groupe P2 1 /n et le compose WBr 2 (CO) 2 (PPh 3 ) 2 dans le systeme triclinique, groupe P1. Affinement des structures jusqu'a R=0,032 et 0,064 respectivement. Le premier compose est diamagnetique a geometrie pseudo-octaedrique. Le second possede une geometrie octaedrique tres deformee
28 citations
TL;DR: In this paper, it was shown that NBD is more easily displaced from PtMe2 (NBD) by other ligands than is cyclooctadiene (COD) from COD, giving cis-Pt(CF3)2L2 (L = py, 1 2tmen,1 2en, NH3, DMSO, NCR, DMF, CN-, I-, acac-).
26 citations
TL;DR: The two component Ziegler catalyst [Rh(acacac)3]-AlEt3 (or an analogue with an alternative cocatalyst) has been investigated for the hydrosilylation by SiHX3 of alkynes, dienes, alkenes, styrene, or allylbenzene at 60°C.
24 citations
TL;DR: In this paper, homogeneous catalytic hydrogenation of 3-methylenecyclohexanol gives trans -3-methylcyclohexanemethanol with 98% stereoselectivity.
23 citations
TL;DR: 1,1-Bis(benzenesulfonyl)ethylene (1) acts as a synthetic equivalent of ethylene 1,2-dipole as it gives with olefins products derived from a postulated dipolar reaction mechanism that can be readily desulfonylated into the formal ethylene adducts as discussed by the authors.
Abstract: Among many coloured norbornadienes which have been synthesized bearing electron-donating and electron-withdrawing substituents, the 2,3-diphenyl-5-methoxycarbonyl-6-propionly derivative was found to satisfy many important requirements for the chemical conversion of solar light energy because of its visible light absorption, a high quantum yield for its photocycloaddition to the corresponding quadricyclane and a rapid and complete reversion of the quadricyclane to the norbornadiene with an acid catalyst
TL;DR: Polymer-supported hydrogen fluoride, in comparison to hydrogen fluoride-pyridine, enhanced the endo attack of the electrophile on norbornadiene by fluorination or halofluorination.
TL;DR: Isomerisation de valence du quadricyclane (Q) en norbornadiene acceleree par irradiation a 313 nm en presence du catalyseur complexe PdCl 2 (η 4 -norbornadiENE) as discussed by the authors.
Abstract: Isomerisation de valence du quadricyclane (Q) en norbornadiene acceleree par irradiation a 313 nm en presence du catalyseur complexe PdCl 2 (η 4 -norbornadiene). Le rendement quantique peut exceder 10 2 et depend de la concentration de Q, de l'intensite lumineuse et du solvant. Mecanisme de reaction en chaine redox
TL;DR: The gas phase reactions of cycloheptatriene and norbornadiene with Co/sup +/ and Rh/sup+/ are described in this article, where the dominant process for Rh/Sup+/ is dehydrogenation, generating a RhC/sub 7/H/sub 6//sup++/ complex.
Abstract: The gas-phase reactions of toluene, cycloheptatriene, and norbornadiene with Co/sup +/ and Rh/sup +/ are described. The dominant process for Rh/sup +/is dehydrogenation, generating a RhC/sub 7/H/sub 6//sup +/ complex. These RhC/sub 7/H/sub 6//sup +/ ions decompose, yielding RhC/sup +/ (benzene loss), presumably through the intermediacy of a carbide-benzene complex. Rh/sup +/ dehydrogenates toulene-..cap alpha..,..cap alpha..,..cap alpha..-d/sub 3/ to eliminate both D/sub 2/ (70%) and HD(30%). Cobalt ions react quite differently with no CoC/sub 7/H/sub 6//sup +/ or CoC/sup +/ observed. Both Co/sup +/ and Rh/sup +/ abstract hydride from cycloheptatriene, implying D/sup 0/(Co-H) > 47kcal/mol. The gas-phase chemistry of Rh/sup +/ is similar to the chemistry observed on metal surfaces for cycloheptatriene and norbornadiene.
TL;DR: A number of new nitrosoarene complexes of rhodium(I) and iridium (I) have been prepared, and characterized by elemental analysis, IR spectroscopy, and 1H NMR as discussed by the authors.
TL;DR: The salt [N(Ph3)2][W(CR)(CO)2(η5-1,2-C2B9H9Me2)](R = C6H4Me-4) reacts with the compounds [RhCl(PPh3]3], [Rh(Pph3) 2(diene)][BF4] as discussed by the authors ] to give products with tungsten-rhodium or tengsten-gold bonds, the structures of which were determined by X-ray diffraction; that from the nor
Abstract: The salt [N(Ph3)2][W(CR)(CO)2(η5-1,2-C2B9H9Me2)](R = C6H4Me-4) reacts with the compounds [RhCl(PPh3)3], [Rh(PPh3)2(diene)][BF4](diene = cyclo-octa-1,5-diene or norbornadiene), and [AuCl(PPh3)] to give products with tungsten–rhodium or tungsten–gold bonds, the structures of which were determined by X-ray diffraction; that from the norbornadiene complex contains a nortricyclane moiety bonded to a boron atom of the C2B9 cage.
TL;DR: The hydrogenation catalyst precursor ClO4 reacts with H2(1 atm, 30 °C, MeOH) to yield [(L−L)HRh(µ-H)3RhH(L-L)]ClO4[L]-L =rac-Fe(η5-C5H4PPhBut)2; NBD = norbornadiene].
Abstract: The hydrogenation catalyst precursor [(L–L)RhNBD]ClO4 reacts with H2(1 atm, 30 °C, MeOH) to yield [(L–L)HRh(µ-H)3RhH(L–L)]ClO4[L–L =rac-Fe(η5-C5H4PPhBut)2; NBD = norbornadiene].
TL;DR: In this article, the displacement of the diene from [M(η4-diene)(CO)4] by phosphorus ligands was investigated and showed that the rate of isomerization increases with the number of ligands.
Abstract: Kinetic studies are reported of the displacement of the diene from [M(η4-diene)(CO)4][diene = norbornadiene, M = Cr, Mo, or W; diene = cyclo-octa-1,5-diene (cod), M = Mo] by phosphorus ligands [L = PBu3, P(OMe)3, or P(OPh)3] to give complexes [M(CO)4L2] With the exception of [Mo(cod)(CO)4], all reactions exhibit a bimolecular rate law of the type –d[A]/dt=Kobs[A][L], where A =[M(diene)(CO)4] which is interpreted mechanistically as a stepwise ligand-assisted dechelation of the diene; kobs may be seen to increase in the order Cr < W Mo, while the ordering in terms of ligand [P(OPh)3 < P(OMe)3 < PBu3] reflects the increasing order of ligand nucleophilicity cis–trans Isomerization of [M(CO)4L2](L = PBu3, P(OMe)3, or P(OPh)3; M = Cr, Mo, or W) has also been studied kinetically With the exception of [Mo(CO)4{P(OPh)3}2], all isomerizations are intramolecular Rates of isomerization increase in the order Mo < W < Cr and in the order P(OPh)3 < P(OMe)3 < PBu3, while Keq(=[trans]/[cis]) increases in the order W ≈ Mo Cr and in the order P(OPh)3 < P(OMe)3 < PBu3 These results are interpreted in terms of both steric and electronic factors
TL;DR: In this article, the crystal and molecular structure of Pd(SNNMe2)(AsPh3)Cl2 was determined from single-crystal X-ray diffraction data.
TL;DR: In this paper, the isomerization of quadricyclene to norbornadiene by a redox chain mechanism is described. But this is not the case in this paper.
TL;DR: L'homo-2 protoadamantadiene-2,5 subit une reaction homo-Diels-Alder avec le TCNE plus rapide que le norbornadiene as discussed by the authors.
Abstract: L'homo-2 protoadamantadiene-2,5 subit une reaction homo-Diels-Alder avec le TCNE plus rapide que le norbornadiene
TL;DR: In this article, the authors used 31P nmr spectroscopy to obtain an activation energy of 102.4 ± 6.0kJm−1 for the release of the NSN fragment from Me2PS3N5.
Abstract: The oxidative addition of Cl2 (using SO2Cl2) to the six-membered ring (R2PN)(SN)2 (R = Me, Ph) produces the mixed phosphazene–thiazyl heterocycles, (R2PN)(NSCl)2, which react with Me3SiNSNSiMe3 to give the bicyclic compounds R2PS3N5. The latter undergo thermal decomposition, at ca. 100 °C in toluene, via reductive elimination of an NSN unit to regenerate (R2PN)(SN)2 in high yield. Kinetic measurements of this process, using 31P nmr spectroscopy, yield an activation energy of 102.4 ± 6.0 kJ mol−1 for the release of the NSN fragment from Me2PS3N5. The thermolysis route has been used to prepare the thermally unstable (F2PN)(SN)2, characterized as a 1:1 adduct with norbornadiene.
TL;DR: In this paper, the tetracarbonyl norbornadiene metal compounds M(CO)4NBD with L at room temperature or 35°C, respectively, have been characterized by analytical and spectroscopic (IR, NMR, MS) methods.
Abstract: Die Komplexe M(CO)4L2 (M Cr, Mo, W; L Me2PSMe, Me2PSeMe, (CF3)2PSMe, (CF3)2PSeMe) werden durch Umsetzung der Norbornadienverbindungen M(CO)4NBD mit L bei Raumtemperatur bzw. bei 35°C dargestellt. Die primar gebildeten cis-Komplexe lagern sich bei erhohter Temperature in die trans-Isomeren um. Die neuen Verbindungen werden analytisch und spektrometrisch (IR, NMR, MS) charakterisiert.
Perfluoromethyl Element Ligands. XXIX. Preparation and Spectroscopic Investigation of M(CO)4L2 Complexes (M Cr, Mo, W; L Me2PSMe, Me2PSeMe, (CF3)2PSMe, (CF3)2PSMe)
The complexes M(CO)4L2 (see Inhaltsubersicht) have been prepared by the reaction of tetracarbonyl norbornadiene metal compounds M(CO)4NBD with L at room temperature or 35°C, respectively. The cis-complexes formed in the first step undergo rearrangement to trans-isomers at higher temperatures. New compounds have been characterized by analytical and spectroscopic (IR, NMR, MS) methods.
TL;DR: The metathesis reactions of cycloolefins results in a ring-chain equilibrium of cyclic oligomers and an acyclic polymer as discussed by the authors, and the distribution of the polymer can be described by a most probable molecular weight distribution.
Abstract: The metathesis reactions of cycloolefins results in a ring-chain equilibrium of cyclic oligomers and an acyclic polymer. The distribution of the polymer can be described by a most probable molecular weight distribution. The oligomer distribution differs in the kinetically controlled regime of the reaction from the equilibrium situation. The particular cases of norbornene and norbornadiene are discussed.
Carbene complexes may be used as initiators. The more stable the carbene the more strained the cycloolefin has to be in order to be polymerizable. With increasing strain the cis-stereoselectivity is significantly attenuated. (CO)5CRCR′R″ may initiate the metathesis reaction of cyclic and acyclic vinylethers. The reaction proceeds in a structurally uniform manner, i.e. only vinylethers are formed, and yields the equilibrium ratio of cis and trans double bonds.
TL;DR: In this article, a mechanism involving an equilibrium between diene-dihydride and alkyl-hydride was proposed, where the dienes 2,3-dimethylbutadiene and cyclohexa-1,3 or -1,4-diene react with (1) to give highly fluxional allylhydride species which feature an aliphatic C-H ⋯ IrIII interaction.
Abstract: Stopped-flow n.m.r. reveals markedly different rates of co-ordination of cyclo-octa-1,5-diene (cod) and bicyclo[2.2.1]hepta-2,5-diene (norbornadiene, nbd) to the ion [Ir(PPh3)2(OCMe2)2H2]+(1). [Ir(PPh3)2(diene)H2]+ ions are the first formed products. The interconversion of all three [Ir(PPh3)2(nbd)H2]+ isomers has been observed by 1H and 31P n.m.r. spectroscopy. These species react further to give [Ir(PPh3)2(nbd)]+(2), either by H2 elimination, or by hydrogenation of the co-ordinated nbd to form bicyclo[2.2.1]hept-2-ene (norbornene, nbe). Stopped-flow spectrophotometry reveals a marked inverse kinetic isotope effect for the formation of (2) during the hydrogenation or deuteriation of nbd. A mechanism involving an equilibrium between diene–dihydride and alkyl–hydride is proposed. The dienes 2,3-dimethylbutadiene and cyclohexa-1,3- or -1,4-diene react with (1) to give highly fluxional allyl–hydride species which feature an aliphatic C–H ⋯ IrIII interaction. Variable-temperature 1H and 31P n.m.r., and 1H spin-saturation transfer experiments reveal a facile reversible hydrogen-transfer process between metal and hydrocarbon ligand which occurs via a C–H ⋯ IrIII interaction.
TL;DR: In this article, the cristallise dans P2 1 /c avec Z=4 was used for cyclooctadiene-1,5 et C 7 H 8 =norbornadiene. Affinement jusqu'a R=0,034; 0,043 et 0,047 respectivement.
Abstract: [RhC 8 H 12 (NH 3 ) 2 .C 28 H 40 O 10 ] [PF 6 ] cristallise dans P2 1 /c avec Z=4. [RhC 8 H 12 (NH 3 ) 2 .C 24 H 32 O 8 ] [PF 6 ] cristallise dans P2 1 /c avec Z=4. [RhC 7 H 8 (NH 3 ) 2 .C 24 H 32 O 8 ] [PF 6 ] cristallise dans Pbca avec Z=8. Affinement jusqu'a R=0,034; 0,043 et 0,047 respectivement. C 8 H 12 =cyclooctadiene-1,5 et C 7 H 8 =norbornadiene
TL;DR: Les reactions de cycloaddition du diiminosuccinonitrile (DISN) avec des olefines nucleophiles donnent une variete de produits parmi lesquels on trouve des cycloadduits [4+2] and des aziridines as mentioned in this paper.
Abstract: Les reactions de cycloaddition du diiminosuccinonitrile (DISN) avec des olefines nucleophiles donnent une variete de produits parmi lesquels on trouve des cycloadduits [4+2] et des aziridines. Une inversion de polarisation de l'une des liaisons C=N du DISN serait responsable des reactions observees