Elemental analysis by NMR.
We explore the possibility for elemental analysis by NMR. To keep the efficiency of the signal acquisition common for all spin species, we propose to fix the frequency and vary the magnetic field to cover the isotopes involved in a sample. We introduce constant-frequency receptivity for quantitative elemental analysis in the frequency-fixed NMR experiment. Field-variable NMR experiments are demonstrated using a cryogen-free superconducting magnet. In addition to elemental analysis in liquid solution, solid-state NMR under magic-angle spinning is also described.
A series of new norspermidine derivatives, both nonionic and cationic, have been obtained. Structures of the synthesized compounds have been established by FTIR, H NMR, C NMR, 2D NMR, mass spectrometry and elemental analyses. Physicochemical and antimicrobial properties have been discussed.متن کامل
Aprotic diazotization of anthranilic acid with isoamylnitrite or amylnitrite gave benzenediazonium-2- carboxylate. Subsequent thermal decomposition of this diazonium salt (in situ) in 1,2-dichloroethane as a solvent at 85OC and in the presence of 2,5-diethyl-3,4-diphenylcyclopentadienonaes a trapping agent gave 1,4-diethyl-2, 3-diphenylnaphthalene in high yield, after loss of carbon monoxid...متن کامل
Synthesis, spectroscopic investigation and coductometry of a new hexadentate symmetric Schiff base ligand containing N2O2S2 donor atoms and related complexes with Cd(II), Zn(II), Co(II) and Mn (II) metal ions
In this paper, we report the synthesis and characterization of a new symmetric macroacyclic Schiff base ligand (H2L) and related complexes with different metals. (H2L) was synthesized by the one pot condensation reaction of 2-[2-(2-formyl phenoxy)ethoxy]benzaldehyde and 2-aminobenzenethiol in a 1:2 molar ratio. The acyclic Schiff base was characterized by IR, NMR spectroscopy and elemental anal...متن کامل
Cross-polarized magic-angle-spinning NMR (CPMAS-NMR) techniques are assumed to be only semi-quantitative in the assessment of carbon distribution in humic substances or natural organic matter, due to a number of interferences such as spinning side bands (SSB) in spectra, paramagnetic species in samples, and low or remote protonation of aromatic carbons. Fast rotor spin rates or direct polarizat...متن کامل
W e encourage our authors to consider the use of absolute quantitative 1 H NMR spectroscopy to determine the purity of biologically tested research compounds. The Perspective by Pauli et al. (DOI: 10.1021/jm500734a) in this issue provides an excellent overview of quantitative 1 H NMR spectroscopy methods and their use for purity determination. The major advantages of these techniques are that t...متن کامل