30810-15-2Relevant academic research and scientific papers
Protonated benzene: A case for structural memory effects?
Schroeder, Detlef,Loos, Jessica,Schwarz, Helmut,Thissen, Roland,Dutuit, Odile
, p. 9931 - 9937 (2008/04/18)
Photoionization tandem-mass spectrometry of selectively deuterium labeled precursor molecules is used to probe the structure of protonated benzene which had been questioned in a provocative publication by Mason and co-workers (J. Chem. Soc., Chem. Commun. 1995, 1027). Specifically, we address the intriguing aspect of a postulated delayed hydrogen ring-walk by modulating the internal energy content of mass-selected C6H7-nDn + ions. To this end, ionization of selectively deuterated precursors by tunable synchrotron photons is combined with chemical monitoring of H +/D+ transfer from C6H7-nD n+ to a strong base B. The resulting BH +/BD+ ratios monotonically decrease with increasing internal energy content and, due to the virtue of the regioselective deuterium label incorporations, thereby disprove a delayed hydrogen ring-walk or any other "structural memory effect" in C6H7-nD n+ ions. As a consequence, the experimental studies of Mason et al. were reconsidered using sector-field mass spectrometry. These extensive studies suggest that the previous observations might have been obscured by a combination of isobaric impurities, metastable-ion contributions, and artifact signals.
Rigid phencyclidine analogues. Binding to the phencyclidine and σ1 receptors
Moriarty, Robert M.,Enache, Livia A.,Zhao, Lei,Gilardi, Richard,Mattson, Mariena V.,Prakash, Om
, p. 468 - 477 (2007/10/03)
Three phencyclidine (PCP) analogues possessing a highly rigid carbocyclic structure and an attached piperidine ring which is free to rotate were synthesized. Each analogue has a specific fixed orientation of the ammonium center of the piperidinium ring to the centrum of the phenyl ring. The binding affinities of the rigid analogues 1-piperidino-7,8- benzobicyclo[4.2.0]octene (14), 1-piperidinobenzobicyclo[2.2.1]heptene (16), and 1-piperidinobenzobicyclo[2.2.2]octene (13) for the PCP receptor ([3H]TCP) and σ-receptor (NANM) were determined. The three analogues show low to no affinity for the PCP receptor but good affinity for the σ-receptor and can be considered σ-receptor selective ligands with PCP/σ ratios of 13, 293, and 368, respectively. The binding affinities for the σ-receptor are rationalized in terms of a model for the σ-pharmacophore.
Condensations of Crotonate Arsonium Ylide with Conjugated Carbonyl Compounds
Moorhoff, Cornelis M.
, p. 126 - 128 (2007/10/03)
Condensations of methyl 4-(triphenylarsoranylidene)-2-butenoate 1a and conjugated carbonyl compounds give 1,3-cyclohexadiene-1-carboxylates and/or acyclic trienes in superior yields compared to the condensations with the phosphonium analogue 1b. However, the reaction of 1a and ethyl 2-cyano-5-methyl-2,4-hexadienoate 7 gave a mixture of two diastereomeric trans-bisvinylcyclopropanecarboxylates 9.
Enzymatic and Nonenzymatic Reactions of 1β--4α-hydroxycyclohex-2-ene-1-carboxylate
Delany, John J.,Berchtold, Glenn A.
, p. 3262 - 3265 (2007/10/02)
The synthesis of disodium 1β--4α-hydroxycyclohex-2-ene-1-carboxylate (4) is described.Compound 4 was synthesized in five steps from 1,4-diol 10, which was prepared in three steps from the known diene 7.Compound 4 undergoes a facile
High Pressure Experiments, XI. Reaction of Phosgene with 1,3-Cyclohexadiene at High Pressure
Kurz, Karlheinz,Plieninger, Hans
, p. 3666 - 3668 (2007/10/02)
Phosgene in toluene reacts at 80 deg C/5000 at with 1,3-cyclohexadiene to yield acyl chlorides.Without pressure no reaction is observed.After esterification the compounds 1-5 could be identified.The Diels-Alder adduct 6 was not observed.
