Showing papers on "Norbornadiene published in 1974"
TL;DR: A number of workers have reported the 13 C NMR spectra of monosubstituted phenyl groups and correlated the shifts with molecular parameters as discussed by the authors, such as the C−H bond length and the C-H stretching force constant.
Abstract: Publisher Summary From the time of the first direct observation of a 13 C nuclear magnetic resonance (NMR) signal in 1957 until about 1968, the use of 13 C NMR spectroscopy was in the hands of the few specialists who were prepared to build their own spectrometers. To maximize sensitivity, it is usual to measure 13 C NMR spectra with complete proton decoupling. Correlations in 13 C chemical shifts found for methyl derivatives of organic compounds may apply to organometallic compounds. A number of workers have reported the 13 C NMR spectra of monosubstituted phenyl groups and correlated the shifts with molecular parameters. The large low-field chemical shifts of 362.3 to 253.7 ppm found for metal–carbene complexes are in the region where signals due to carbonium ions are found. The variation in Z eff can account for only a very small fraction of the total change and may even be neglected in most cases. l J( 13 C – l H) has also been related to the C–H bond length and the C–H stretching force constant. The magnitude of the olefin coordination shift appears to approximately correspond to the strength of the olefin–metal interaction, with the smallest coordination shifts being found for the weak silver–olefin complexes, and the largest coordination shift being found for the very strong rhodium–norbornadiene complex [(norbornadiene)Rh(C 5 H 5 )].
105 citations
47 citations
TL;DR: In this paper, the stereospecific exchange of acetonitrile ligands in the cationic species was described and discussed, including a reinterpretation of those for the Ru(diene)(π-allyl)2 species.
Abstract: Monocationic ruthenium(II) and osmium(II) complexes containing labile acetonitrile ligands have been prepared by electrophilic attack on a π-allyl ligand in M (diene)(π-allyl), species (M = Ru or OS, diene = norbornadiene or cyclo-octa-1,5-diene). The acetonitrile ligands may be replaced by Group VA chelating ligands. The allyl ligand in the monocationic species is also attacked by electrophiles to yield dicationic complexes. The stereospecific exchange of acetonitrile ligands in the cationic species is described. N.m.r. data, including a reinterpretation of those for the Ru(diene)(π-allyl)2 species, are presented and discussed.
37 citations
TL;DR: The photoelectron spectra of quadricyclane (3) and 3-methylidene (4) have been measured and the results served as a basis for the elucidation of the electronic structure of these compounds, which agreed with theoretical calculations as discussed by the authors.
Abstract: The photoelectron spectra of quadricyclane (3) and 3-methylidene quadricyclane (4) have been measured. The results served as a basis for the elucidation of the electronic structure of these compounds, which agreed with theoretical calculations. It is found that the symmetry of the HOMO of 3 is different when compared to that of its valence isomer norbornadiene (1). The results also indicate that the structure of the highest occupied orbitals cannot be derived by only considering the Walsh-orbitals of the two three-membered rings. In addition one of the Walsh-components of the four-memebered ring has to be taken into account.
32 citations
TL;DR: In this paper, the exo-trans-exo configuration of a mixture of benzonorbornadiene with enneacarbonyldiiron, Fe2(CO)9, at room temperature gave tetracarbonyl(l, 4-dihydro-1,4-epoxynaphthalene)iron, in which the olefinic δ-bond is bonded to the metal.
Abstract: Reaction of benzonorbornadiene, 7-isopropylidenebenzonorbornadiene (1,4-dihydro-9-isopropylidene-1,4-methanonaphthalene) and 1,4-dihydro-1,4-epoxynaphthalene (7-oxabenzonorbornadiene) with dicarbonyldinitrosyliron, Fe(CO)2(NO)2, gave in good yields the corresponding dimers having the exo-trans-exo configuration. Treatment of a mixture of benzonorbornadiene and norbornadiene with Fe(CO)2(NO)2 gave a 'crossed dimer', in addition to the dimers derived from benzonorbornadiene and norbornadiene. The reaction of benzonorbornadiene with pentacarbonyliron at 100o gave the exo-trans-exo dimer and a ketone derived by dimerization and carbonyl insertion. This ketone, and the analogous ketone obtained from 7-isopropylidenebenzonorbornadiene, have been assigned the exo-trans-exo configuration. Reaction of 1,4-dihydro-1,4-epoxynaphthalene with enneacarbonyldiiron, Fe2(CO)9, at room temperature gave tetracarbonyl(l,4-dihydro-l,4-epoxynaphthalene)iron(0), in which the olefinic ח-bond is bonded to the metal. In solution at 63o this complex gave naphthalene.
31 citations
TL;DR: In this article, the basic structures of the present clustet carbonyls are either retained or broken down, in which the plausible structures for these complexes are discussed on the basis of IR, NMR, and mass spectrometric data.
30 citations
TL;DR: In this article, the reactions of [C 5 H 5 Ni(Diene)]BF 4 (Diene = norbornadiene or 1,5-cyclooctadiene) with the methoxide anion OMe − in methanol give the uncharged complexes C 5H 5 NiC 7 H 8 OMe (IV) and C 5 H5 NiC 8 H 12 OME (VI) respectively.
28 citations
TL;DR: In this article, it was found that carbenes undergo extensive addition to the endo-face of norbornadiene, yeilding the cheletropic adduct, 4.4-difluorotetracyclo[3.3.0.02,8.03,6]-octane.
Abstract: It has been found that difluorocarbene undergoes extensive addition to the endo-face of norbornadiene, yeilding the cheletropic adduct, 4.4-difluorotetracyclo[3.3.0.02,8.03,6]-octane. Similar behaviour has been observed for fluorochlorocarbene. Possible mechanisms to rationalize this novel behaviour of carbenes are discussed.
26 citations
23 citations
TL;DR: The structure of the ruthenium complex has been determined from three-dimensional X-ray data collected by counter techniques and refined by a least-squares procedure to a conventional agreement index of 0.025 as mentioned in this paper.
23 citations
TL;DR: In this article, the reactions of norbornadiene in amine by the use of nickel, palladium and rhodium complexes have been studied in the presence of protic acid.
Abstract: The reactions of norbornadiene in amine by the use of nickel, palladium and rhodium complexes have been studied in the presence of protic acid. A catalytic system of Ni(COD)2 (1)-n-Bu3P gives a mixture of 5-exo-(o-tolyl)-2-norbornene (3) and 5-exo-(N-amino)-2-norbornene (4). Bis(triphenylphosphine)(maleic anhydride)palladium (5) gives 3-(N-amino)nortricyclene (6). Dichlorotetrakis(cyclooctene)dirhodium (10) gives a [2+4] cycloaddition product (11). All these reactions mechanisms are discussed from the point of view of an acid-promoted reaction on low-valent transition metal complexes.
TL;DR: In this paper, a treatment of nonconjugated olefins such as cis- and trans-2butenes, cis-2-octene, and cyclohexene with MoCl5 in CCl4 gave vic-dichloroalkanes whose cis-isomer was formed predominantly.
Abstract: Treatment of nonconjugated olefins such as cis- and trans-2-butenes, cis-2-octene, and cyclohexene with MoCl5 in CCl4 gave vic-dichloroalkanes whose cis-isomer was formed predominantly, the ratio of cis- to trans-addition being 4.9–12.1, together with monochloroalkanes. Preferential formation of exo-cis-dichloride was observed in the case of norbornene and norbornadiene. Bromochlorination and chloroiodination of olefins, and aromatic bromination and iodination were carried out with mixtures of MoCl5 and halogens. The reaction scheme for chlorination is discussed.
TL;DR: In this paper, data on 13C chemical shifts and 13C1H spin coupling constants of norbornane (1), norbornene (2) and norbornadiene (3), benzonorbornen (4), and benzonorsorbornadienes (6) are reported.
Abstract: Data on 13C chemical shifts and 13C1H spin coupling constants of norbornane (1), norbornene (2), norbornadiene (3), benzonorbornene (4) and benzonorbornadiene (6) are reported. The non-equivalence in J(13CH) values determined from the two bridge methylene proton signals in 2,2,3,3-tetradeuteriobenzonorbornene (5) and 6 is briefly discussed. The extraordinary deshielding of the bridge methylene carbon in 6 has been noted.
TL;DR: In amine norbornadiene is converted catalytically into exo -5-(o-tolyl) - 2 - norbornene by (n-Bu3P)2NiX2- NaBH4.
TL;DR: In contrast to the normal addition mode of hexachlorocyclopentadiene (3) to norbornadiene, which yields mainly (but not exclusively) aldrin having the endo-exo-1,4:5,8-dimethanonaphthalene skeleton, the reaction of as mentioned in this paper with norbornadien-7-yl acetate gives three adducts: 1,2,3,4,10, 10,10-hexachloro, 1, 4,4a, 5,8, 8,
Abstract: In contrast to the normal addition mode of hexachlorocyclopentadiene (3) to norbornadiene, which yields mainly (but not exclusively) aldrin having the endo-exo-1,4:5,8-dimethanonaphthalene skeleton, the reaction of (3) with norbornadien-7-yl acetate gives three adducts: 1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-endo-endo-1,4:5,8-dimethanonaphthalen-syn-9-yl and -anti-9-yl acetates [(7) and (9)] and the 'normal' 1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-endo-exo-1,4:5,8-dimethanonaphthalen-syn-9-yl acetate (11). The addition of (3) to 7-t-butoxynorbornadiene yields mainly the anti-9-t-butoxy-endo-endo adduct, analogous to (9), while the addition of (3) to 7-methylnorbornadiene gives mainly syn-9-methyl-endo-exo-adduct,analogous to (11). The structure of these adducts has been determined by spectroscopic (N.M.R. and infrared) and chemical (photochemicalcyclization of the endo-endo systems) means.
TL;DR: In this paper, a reaction of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene with norbornadiene and benzo-norbornadienes gave adducts having the endo-exo-1,4,4a,5,8,8-8a-hexahydro, 1,4:5, 8-dimETHano-naphthalene, and endoexo -1, 4, 4a,9, 9, 9a,
Abstract: Reaction of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene with norbornadiene and benzo-norbornadiene gave adducts having the endo-exo-1,4,4a,5,8,8a-hexahydro-1,4:5,8-dimethano-naphthalene and endo-exo-1,4,4a,9,9a,l0-hexahydro-1,4:9,l0-dimethanoanthracene skeletons, respectively. These adducts were dechlorinated to give acetals, which were hydrolysed to give the corresponding ketones. The initial adducts, and the derived acetals and ketones, are all sterically compressed as a result of crowding of the C2-C3 etheno bridge against a methano hydrogen atom syn to that bridge. This steric compression manifests itself in a marked deshielding of the relevant methano proton in the N.M.R. spectra of these compounds, and in an increased rate of thermal decarbonylation of the ketones. The location of the deuterium atom in benzonorbornadiene[7-anti-D] (12) has been established chemically by observing an intramolecular deuterium transfer during photochemical half-cage formation from the adduct of (12) and 1,2,3,4-tetrachloro-5,5- dimethoxycyclopentadiene.
TL;DR: In this paper, the anti/syn ratio of the cycloadducts is discussed in terms of steric and electronic factors for alkyldiazomethylphosphonates.
Abstract: The addition of 14 dimethyl aryl- and alkyldiazomethylphosphonates, RC(N2)P(O)(OCH3)2, to norbornadiene has been studied and the stereochemistry of the resulting exo-Δ1-pyrazolines determined by n.m.r. The anti/syn ratio of the cycloadducts is discussed in terms of steric and electronic factors. For alkyldiazomethylphosphonates steric factors are the dominant ones, while with aryldiazomethylphos-phonates electronic factors seem to be of importance.
TL;DR: Using PtCH3(NBD)I (NBD = norbornadiene) as starting material, compounds of the type PtCH 3L2I (L2 = 1,5-cyclooctadiene and N,N,N′, N′-tetramethylethylenediamine, L = 3,5lutidine and benzylamine) have been prepared and characterized by 1H NMR and elemental analysis as mentioned in this paper.
TL;DR: In this article, it was shown that 2-(MeR 1 CCR 2 )-pyridine undergoes a 1,3-double-bond shift on displacement of norbornadiene from [M(CO) 4 norb] (M = Cr, Mo or W) to give complexes of the type [M[CO] 4 LL'] (LL' = 2-(allyl)or 2-(substituted allyl)-Pyridine), which do not exhibit conformational isomerism involving the plane of the coordinated o
TL;DR: In this article, photolysis of 2,3-diphenylnaphthoquinone oxide resulted in carbon-carbon bond cleavage to give a seven-membered mesoionic benz[d]oxepine-1,5-dione intermediate, which was trapped by Nphenylmaleimide and norbornadiene.
Abstract: Photolysis of 2,3-diphenylnaphthoquinone oxide resulted in carbon–carbon bond cleavage to give a seven-membered mesoionic benz[d]oxepine-1,5-dione intermediate, which was trapped by N-phenylmaleimide and norbornadiene.
Patent•
17 Apr 1974TL;DR: The 2-(4-hydroxy-4-methylpentyl) norbornadiene process for preparing said compound was described in this paper, with the process consisting of two steps:
Abstract: The novel compound, 2-(4-hydroxy-4-methylpentyl) norbornadiene, process for preparing said compound comprising the steps of:
TL;DR: Octachorofulvalene reacted readily as a dienophile with conjugated olefins to afford (2 + 4) mono-and di-adducts, but it reacted as the diene component with norbornadiene.
Abstract: Octachorofulvalene reacted readily as a dienophile with conjugated olefins to afford (2 + 4) mono- and di-adducts, but it reacted as the diene component with norbornadiene; in contrast, decachloro-2,5-dihydrofulvalene and hexachlorofulvene reacted predominantly as dienic partners with cyclopentadiene.
TL;DR: In this paper, a four-pot synthesis from norbornadiene of the γ-lactones is described, which is useful as prostaglandin precursors.
Abstract: Efficient four-pot syntheses from norbornadiene of the γ-lactones (7), (8), and (2), which are useful as prostaglandin precursors, are described.
TL;DR: In this paper, a reaction of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene with norbornadiene and benzo-norbornadienes gave adducts having the endo-exo-1,4,4a,5,8,8-8a-hexahydro, 1,4:5, 8-dimETHano-naphthalene, and endoexo -1, 4, 4a,9, 9, 9a,
Abstract: Reaction of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene with norbornadiene and benzo-norbornadiene gave adducts having the endo-exo-1,4,4a,5,8,8a-hexahydro-1,4:5,8-dimethano-naphthalene and endo-exo-1,4,4a,9,9a,l0-hexahydro-1,4:9,l0-dimethanoanthracene skeletons, respectively. These adducts were dechlorinated to give acetals, which were hydrolysed to give the corresponding ketones. The initial adducts, and the derived acetals and ketones, are all sterically compressed as a result of crowding of the C2-C3 etheno bridge against a methano hydrogen atom syn to that bridge. This steric compression manifests itself in a marked deshielding of the relevant methano proton in the N.M.R. spectra of these compounds, and in an increased rate of thermal decarbonylation of the ketones. The location of the deuterium atom in benzonorbornadiene[7-anti-D] (12) has been established chemically by observing an intramolecular deuterium transfer during photochemical half-cage formation from the adduct of (12) and 1,2,3,4-tetrachloro-5,5- dimethoxycyclopentadiene.