hydrogen isotope
Iridium(I)-catalyzed Regioselective C-H Activation and Hydrogen Isotope Exchange of Non-aromatic Unsaturated Functionality
... [4] For examples of Ir complexes showing stoichiometric olefinic C-H insertion, see: a) P. O. Stoutland, R. G. Bergman, J. Am. Chem. Soc. 1988, 110, 5732-5744; b) D. Hermann, M. Gandelman, H. Rozenberg, L. J. W. Shimon, ...
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Hydrogen isotope geochemistry of the mantle: constraints from back arc basin basalts and mantle xenoliths
... H isotope geochemistry differs in one important respect from its O isotope geochemistry: metamorphic, melting, and metasomatic processes—generally considered unimportant for most recognized oxygen ...
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The synthesis of highly active iridium(I) complexes and their application in catalytic hydrogen isotope exchange
... By embedding a bulky N-heterocyclic carbene ligand in combination with different phosphine ligands, a series of highly active iridium-based catalysts have been developed for hydrogen isotope exchange. Such ...
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Practically convenient and industrially-aligned methods for iridium-catalysed hydrogen isotope exchange processes
... iridium-catalysed hydrogen isotope exchange reaction with developing phosphine/NHC Ir(I) complexes has identified reaction media which are more widely applicable and industrially acceptable than the ...
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Hydrogen isotope exchange with highly active iridium(I) NHC/phosphine complexes : a comparative counter-ion study
... undergo hydrogen isotope exchange with an iridium(I) NHC/phosphine complex bearing the less coordinating tetrakis[3,5- bis(trifluoromethyl)phenyl]borate counterion, and compare these with labelling using ...
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The development and use of novel iridium complexes as catalysts for ortho-directed hydrogen isotope exchange reactions
... As detailed here, this collaborative programme of work has revealed the considerable efficiency and general applicability of the specific group of novel iridium(I) complexes 4a-c within iridium-catalysed C-H activation ...
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Anion effects to deliver enhanced iridium catalysts for hydrogen isotope exchange processes
... in hydrogen isotope exchange has demonstrated improved catalytic activity at lower catalyst loadings in the order X = BArF ≈ OTf > PF 6 > BF 4 ...
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Iridium-catalyzed Csp3-H activation for mild and selective hydrogen isotope exchange
... A. Hydrogen Isotope Exchange at Alkyl Posi- tions Using Crabtree's Catalyst and its Application to the Tritiation of ...Direct Hydrogen Isotope Exchange ...
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Site-selective deuteration of N-heterocycles via iridium-catalyzed hydrogen isotope exchange
... years, hydrogen isotope exchange (HIE), via metal-catalyzed C − H activation, has been widely adopted as a key method for the synthesis of isotopically labeled compounds, allowing late-stage incorporation ...
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C–H functionalization for hydrogen isotope exchange
... involving hydrogen isotopes makes their installation an important and continuing challenge to synthetic ...transformation, hydrogen isotope exchange requires a continually evolving preparative ...
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Unexplained hydrogen isotope offsets complicate the identification and quantification of tree water sources in a riparian forest
... against hydrogen iso- topes about 10 times more than oxygen isotopes during water uptake, and this discrimination increased with soil water loss, porosity and particle ...
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Stable oxygen and hydrogen isotope fractionation factors for the Goethite (hematite)-water system
... O isotope analysis, respectively, under the oxygen free ...the isotope ratio mass spectrometry (IRMS). The isotope ratios are presented in the delta notation as given ...
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Expanded applicability of iridum(I) NHC-phosphine catalysts in hydrogen isotope exchange processes with pharmaceutically-relevant heterocycles
... Employing this catalyst, competition studies between simple phenyl N-heterocycles revealed that directing group selectivity has to be considered on a case by case basis and cannot be pre[r] ...
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Kinetics of Hydrogen Isotope Absorption for Well Annealed Palladium Platinum Alloys
... dilute hydrogen concentration region in a temperature region from 274 to 357 K by means of constant volume method, where samples were annealed well at 973 K under vacuum before measurements to remove defects ...
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Bipolar carbon and hydrogen isotope constraints on the Holocene methane budget
... Figure 3. Data and inversion. The panels on the left (a–c) show the concentration and the two stable isotope signatures of CH 4 measured in ice cores representing the tropospheric values over the Holocene. The ...
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Fulcher-α Band Spectra in Mixed Hydrogen Isotope Plasmas
... excited hydrogen molecules play significant roles in the molecular assisted recombination (MAR) process, and in the production of the so-called Franck- Condon atoms which determine the neutral penetration depth ...
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Continuous-flow isotope ratio mass spectrometry method for carbon and hydrogen isotope measurements on atmospheric methane
... Fig. 1. Scheme of the online methane analysis system: methane from the sample air stored in the sample loop is isolated from other air components by subsequent preconcentration, cryofocussing and gas chromatographic ...
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Oxygen, carbon and hydrogen isotope studies of contact metamorphism
... TABLE 1 3 O xygen isotope temperatures of f ormation of mineral pairs in the intru s i ons and contact metamorphic aureoles com- pared with heat flow temperatures a[r] ...
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Oxygen and Hydrogen Isotope Ratios in Sedimentary Rocks and Minerals
... The clay mineral suites of the ocean sediments cannot therefore be interpreted as being entirely composed of minerals in isotopic equilibrium with sea water or w[r] ...
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Eruptive shearing of tube pumice: pure and simple
... and hydrogen isotope composition of tube pumice (stars; L: fresh glass, W: weathered sample), meteoric waters in equilibrium with the glasses, and present-day local me- teoric ...
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