𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Theoretical and experimental NMR study of protopine hydrochloride isomers

✍ Scribed by Jaromír Toušek; Kateřina Maliňáková; Jiří Dostál; Radek Marek

Publisher
John Wiley and Sons
Year
2005
Tongue
English
Weight
107 KB
Volume
43
Category
Article
ISSN
0749-1581

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The ^1^H and ^13^C NMR chemical shifts of cis‐ and trans‐protopinium salts were measured and calculated. The calculations of the chemical shifts consisted of conformational analysis, geometry optimization (RHF/6–31G** method) and shielding constants calculations (B3LYP/6–31G** method). Based on the results of the quantum chemical calculations, two sets of experimental chemical shifts were assigned to the particular isomers. According to the experimental results, the trans‐isomer is more stable and its population is ∼68%. Copyright © 2005 John Wiley & Sons, Ltd.

📜 SIMILAR VOLUMES

Experimental and theoretical NMR study o
Experimental and theoretical NMR study of selected oxocarboxylic acid oximes
✍ Kamilla Malek; Martin Vala; Henryk Kozłowski; Leonard M. Proniewicz 📂 Article 📅 2003 🏛 John Wiley and Sons 🌐 English ⚖ 214 KB

## Abstract ^1^H and ^13^C NMR spectra of the oxocarboxylic acid oximes 2‐hydroxyiminopropanoic acid (**1**), 2‐(4‐methylthiazol‐2‐yl)‐2‐(hydroxyimino)acetic acid (**2**) and 2‐cyano‐2‐(hydroxyimino)acetic acid (**3**) were measured in DMSO‐__d__~6~, D~2~O and acetone‐__d__~6~ solutions. The data i

Theoretical and experimental studies of
Theoretical and experimental studies of the diketene system: Product branching decomposition rate constants and energetics of isomers
✍ Binh Bui; Ti Jo Tsay; M. C. Lin; C. F. Melius 📂 Article 📅 2007 🏛 John Wiley and Sons 🌐 English ⚖ 401 KB

## Abstract The kinetics and mechanism for the thermal decomposition of diketene have been studied in the temperature range 510–603 K using highly diluted mixtures with Ar as a diluent. The concentrations of diketene, ketene, and CO~2~ were measured by FTIR spectrometry using calibrated standard mi

Optimizing the13C–14N REAPDOR NMR Experi
Optimizing the13C–14N REAPDOR NMR Experiment: A Theoretical and Experimental Study
✍ Yong Ba; Hsien-Ming Kao; Clare P. Grey; Lamy Chopin; Terry Gullion 📂 Article 📅 1998 🏛 Elsevier Science 🌐 English ⚖ 251 KB

The optimum 14 N pulse lengths in the 13 C-14 N rotationalecho adiabatic-passage double-resonance (REAPDOR) NMR experiment are determined from calculations and from experiments on samples of glycine and L-alanine. The REAPDOR experiment utilizes the adiabatic passages that 14 N spins make between th

C3H4: Theoretical study of structures an
C3H4: Theoretical study of structures and stabilities of isomers
✍ Rita Kakkar; Bhabani S. Padhi 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 626 KB

The various isomers including stable structures, carbenes, and diradicals on the C,H, surface have been investigated. The two carbenes propenylidene and cyclopropylidene have been found to have singlet ground states. Vinylmethylene is predicted to have a triplet ground state with a planar diradical

THEORETICAL AND EXPERIMENTAL STUDY OF MO
THEORETICAL AND EXPERIMENTAL STUDY OF MODAL STRAIN ANALYSIS
✍ L.Y. Yam; T.P. Leung; D.B. Li; K.Z. Xue 📂 Article 📅 1996 🏛 Elsevier Science 🌐 English ⚖ 442 KB

The relationship between the strain mode and displacement mode for vibrating elastic structures is derived. It is based on the idea that when a structure is subjected to dynamic loading, its strain response can be expressed by the superposition of contributions from the ''natural strain modes''. Bot