Isotope Shift in the Proton Magnetic Resonance of CH4, CH3D, CH2D2, and CHD3

Abstract

Articles you may be interested inElectronic spectra of the heteroisotopic CH2D and CHD2 radicals by resonance enhanced multiphoton ionization

Nuclear magnetic resonance isotope chemical shifts in BH4-, CH4and NH4+

“…Previous measurements [4,5] on BH4-and CH4 have shown that monosubstitution causes a shift of 0-015 to 0.020 p.p.m, to higher magnetic field and that the shift is proportional to the degree of substitution. In NH4 + a shift of 0.015 p.p.m, in the opposite direction, i.e.…”

Synthesis of 5-epi-[6-2H2]Valiolone and Stereospecifically Monodeuterated 5-epi-Valiolones: Exploring the Steric Course of 5-epi-Valiolone Dehydratase in Validamycin A Biosynthesis

“…Treatment of 18 with Zn/ND 4 Cl/D 2 O/THF and NiCl 2 at room temperature for 16 h gave tetrabenzyl-5- epi -[6β- 2 H 1 ]valiolone ([6β- 2 H 1 ]- 15 ) with 93 atom % D and 81% de, based on the integration of its 1 H NMR signals (Figure ). The 6-Heq in [6β- 2 H 1 ]- 15 appeared as a singlet (2.64 ppm), instead of a doublet (2.66 ppm) in 15 , shifted upfield around 0.02 ppm due to the deuterium isotope effect . Purification of the synthesis product was carried out using ODS C 18 reversed-phase column chromatography or HPLC to avoid epimerization and wash out of the isotope.…”

The interaction of hexaphenylcarbodiphosphorane with the trimethylplatinum(IV) cation

“…13•14 If an appreciable amount of CH3D had formed (through reaction with solvent), 2H coupling to the remaining protons should have been observed (2/Hcd = 1.9 Hz). 15 The spectrum is measured on a 100-MHz pulsed Fourier transform instrument to greatly enhance the signal-to-noise ratio, and no evidence for 2H coupling is observed. Furthermore, treatment of 3 equiv of C(PPh3)2 with [Me3PtI]4 in THF-ds in a sealed NMR tube shows a singlet at 5(Me4Si) +0.18 ppm.…”