19398-83-5Relevant articles and documents
Determination of dicyclopentadiene and its derivatives as compounds causing odors in groundwater supplies
Ventura, Francesc,Romero, Jordi,Pares, Joan
, p. 2368 - 2374 (1997)
A study of organic pollutants causing odor events in the groundwater from the Lower Llobregat aquifer system has been conducted. This aquifer acts as water reserve of Barcelona (northeast Spain) when the quality of the raw water from the Llobregat River is low. Closed-loop stripping analysis (CLSA), purge-and-trap (P and T), sensory GC, and flavor profile analysis (FPA) have been used as analytical methodologies to identify the compounds responsible for the odor events. Industrial organochlorinated solvents-di-to hexachlorinated saturated and unsaturated hydrocarbons-dioyclopentadiene (DCPD) and its derivatives 8-dihydroD-CPD, tetrahydroDCPD, and adamantane (the trimer of DCPD) are among the most significant compounds identified in the groundwater. DCPD with a mean concentration of 1 μg/L in almost all analyzed wells is the compound causing the odor incidents, regardless that some organochlorinated solvents such as 1,1,2-trichloroethane, trichloroethylene, and perchloroethylene might be even 2 or 3 orders of magnitude more concentrated than DCPD. The synthesis of dihydroDCPD was performed for confirmatory purposes. Trained and untrained panelists have established the threshold odor for this compound in the range of 1025 ng/L. Although further research is needed, it is possible that an illegal landfill closed in the 1970s could be the origin of the different pollutants found. A study of organic pollutants causing odor events in the groundwater from the Lower Llobregat aquifer system has been conducted. This aquifer acts as water reserve of Barcelona (northeast Spain) when the quality of the raw water from the Llobregat River is low. Closed-loop stripping analysis (CLSA), purge-and-trap (P&T), sensory GC, and flavor profile analysis (FPA) have been used as analytical methodologies to identify the compounds responsible for the odor events. Industrial organochlorinated solvents - di- to hexachlorinated saturated and unsaturated hydrocarbons - dicyclopentadiene (DCPD) and its derivatives 8-dihydroD-CPD, tetrahydroDCPD, and adamantane (the trimer of DCPD) are among the most significant compounds identified in the groundwater. DCPD with a mean concentration of 1 μg/L in almost all analyzed wells is the compound causing the odor incidents, regardless that some organochlorinated solvents such as 1,1,2-trichloroethane, trichloroethylene, and perchloroethylene might be even 2 or 3 orders of magnitude more concentrated than DCPD. The synthesis of dihydroDCPD was performed for confirmatory purposes. Trained and untrained panelists have established the threshold odor for this compound in the range of 10-25 ng/L. Although further research is needed, it is possible that an illegal landfill closed in the 1970s could be the origin of the different pollutants found.
Iridium(I) complexes with anionic N-heterocyclic carbene ligands as catalysts for the hydrogenation of alkenes in nonpolar media
Kolychev, Eugene L.,Kronig, Sabrina,Brandhorst, Kai,Freytag, Matthias,Jones, Peter G.,Tamm, Matthias
supporting information, p. 12448 - 12459 (2013/09/23)
A series of lithium complexes of anionic N-heterocyclic carbenes that contain a weakly coordinating borate moiety (WCA-NHC) was prepared in one step from free N-heterocyclic carbenes by deprotonation with n-butyl lithium followed by borane addition. The reaction of the resulting lithium-carbene adducts with [M(COD)Cl]2 (M = Rh, Ir; COD = 1,5-cyclooctadiene) afforded zwitterionic rhodium(I) and iridium(I) complexes of the type [(WCA-NHC)M(COD)], in which the metal atoms exhibit an intramolecular interaction with the N-aryl groups of the carbene ligands. For M = Rh, the neutral complex [(WCA-NHC)Rh(CO)2] and the ate complex (NEt4)[(WCA-NHC) Rh(CO)2Cl] were prepared, with the latter allowing an assessment of the donor ability of the ligand by IR spectroscopy. The zwitterionic iridium-COD complexes were tested as catalysts for the homogeneous hydrogenation of alkenes, which can be performed in the presence of nonpolar solvents or in the neat alkene substrate. Thereby, the most active complex showed excellent stability and activity in hydrogenation of alkenes at low catalyst loadings (down to 10 ppm).
Kinetic isotope effect in the hydrogenation of tricyclo-(5,2,1,02.6)-deca-3,8-diene on platinum metals
Ualikhanova, A.,Temirbulatova, A. E.,Dembitskii, A. A.,Mailyubaev, B. T.,Korolev, A. V.
, p. 240 - 242 (2007/10/02)
The hydrogenation of dicyclopentadiene 21.6)-deca-3,8-diene> by protium and deuterium on Pt, Pd, Ir, Rh, and Ru blacks in hexane at atmospheric or higher hydrogen pressures has been studied at 298-423 K.The kinetic isotope effect has been shown to vary from 1.33 to 2.50 according to the nature of the metal.The main product of complete hydrogenation is endo-tetrahydrodicyclopentadiene 2.6)-decane>: its yield under comparable conditions is higher in a deuterium atomosphere than in the presence of protium.
