Factors Affecting Conformation of ( R,R )-Tartaric Acid Ester, Amide and Nitrile Derivatives. X-Ray Diffraction, Circular Dichroism, Nuclear Magnetic Resonance and Ab Initio Studies
Chlorahupetones A-I (1−9), nine sesquiterpenoid dimers, were isolated from Chloranthus henryi var. hupehensis. Their structures were characterized by nuclear magnetic resonance (NMR), electronic circular dichroism (ECD), and X-ray diffraction analysis....
Tautomerism of dibenzothiazolylmethane (1) and its C-methyl derivative (2) has been studied by 1H nuclear magnetic resonance, ultraviolet, and infrared spectroscopy using C,C-dimethyl (3) and N-methyl (4) derivatives as model compounds of the "CH" and "NH" forms, respectively. X-ray diffraction analysis of the "fixed" N-methyl derivative 4 shows that it corresponds to the Z-sE isomer 4b2. The CH tautomers are unstable in solution and they slowly isomerize into a mixture of NH tautomers that depends on the solvent and on the C-substituent (H or CH3).
A Combined Solid-State Nuclear Magnetic Resonance and in Situ X-Ray
Diffraction Study of the Lithium Deintercalation Mechanism for LiFexCo1-XPO4
(0 ≤ x ≤ 1)