An easily-assembled Soxhlet extractor to demonstrate continuous extraction

The authors thank the Engineering and Physical Sciences Research Council, University of St Andrews, and the CRITICAT Centre for Doctoral Training for financial support [Grant EP/L016419/1].The construction of a Soxhlet extractor from readily available laboratory equipment is described. The apparatus can be used to demonstrate the concept of continuous extraction and was used in the isolation of trimyristin from nutmeg.PostprintPeer reviewe

Heteronuclear bimetallic complexes with 3d and 4f elements

Three heteronuclear bimetallic complexes [Cu(MeOH)(L)Ln(NO3)3] ( 1-Ce ; Ln = Ce, 1-Pr ; Ln = Pr, and 1-Nd ; Ln = Nd) were prepared using H2L (1,3-bis[(3-methoxysalicylidene)amino]-2,2-dimethylpropane) in methanol, affording the complexes as green crystalline materials. These can be prepared in a one-pot synthesis from 2,2-dimethylpropan-1,3-diamine, o-vanillin, copper(II) nitrate, and Ln(III) nitrate (Ln = Ce, Pr, Nd). X-ray crystallography, high-resolution mass spectrometry, and UV-vis spectroscopy were used to characterize the bimetallic complexes. All three complexes showed the copper center adopting a five-coordinate square pyramidal geometry and the lanthanoid cation adopting a ten-coordinate geometry.Publisher PDFPeer reviewe

(9R,9aS,12aR,13S)-9,13-Diphenyl-9,9a,12a,13-tetrahydro-9,13-methanotriphenyleno[2,3-c]furan-10,12,14-trione

X-ray crystallography was used to characterise the title compound for the first time, and the 1H NMR, 13C NMR and IR spectroscopic data from earlier reports were also updated.Publisher PDFPeer reviewe

Rječnik hrvatskoga ili srpskoga jezika dovršen

Simple protocols have been devised for peroxyoxalate chemiluminescence demonstrations that use urea–hydrogen peroxide or sodium percarbonate as oxidants in place of aqueous solutions of hydrogen peroxide. The procedures described are compatible with well-known peroxyoxalates and fluorescers and have been found to be convenient for use for outreach activities in venues with limited laboratory facilities.PostprintPeer reviewe

Calculation and experimental measurement of paramagnetic NMR parameters of phenolic oximate Cu(II) complexes

This work was supported by the EPSRC through the Collaborative Computational Project on NMR Crystallography (CCP-NC), via EP/M022501/1. SEA would also like to thank the Royal Society and Wolfson Foundation for a merit award. MB would like to thank EaStCHEM and the School of Chemistry for support and access to a computer cluster maintained by Dr. H. Früchtl. ZK gratefully acknowledges a scholarship from the China Scholarship Council. For research data supporting this publication see DOI: http://dx.doi.org/10.17630/9061ace0-88fb-4a55-a1eb-05e020f369fd.We present a strategy for predicting the unusual 1H and 13C shifts in NMR spectra of paramagnetic bisoximato copper(II) complexes using DFT. We demonstrate good agreement with experimental measurements, although 1H-13C correlation spectra show that a combined experimental and theoretical approach remains necessary for full assignment.PostprintPostprintPeer reviewe

High-resolution solid-state 13C NMR spectroscopy of the paramagnetic metal-organic frameworks, STAM-1 and HKUST-1

Solid-state C-13 magic-angle spinning (MAS) NMR spectroscopy is used to investigate the structure of the Cu(II)-based metal-organic frameworks (MOFs), HKUST-1 and STAM-1, and the structural changes occurring within these MOFs upon activation (dehydration). NMR spectroscopy is an attractive technique for the investigation of these materials, owing to its high sensitivity to local structure, without any requirement for longer-range order. However, interactions between nuclei and unpaired electrons in paramagnetic systems (e.g., Cu(II)-based MOFs) pose a considerable challenge, not only for spectral acquisition, but also in the assignment and interpretation of the spectral resonances. Here, we exploit the rapid T-1 relaxation of these materials to obtain C-13 NMR spectra using a spin-echo pulse sequence at natural abundance levels, and employ frequency-stepped acquisition to ensure uniform excitation of resonances over a wide frequency range. We then utilise selective C-13 isotopic labelling of the organic linker molecules to enable an unambiguous assignment of NMR spectra of both MOFs for the first time. We show that the monomethylated linker can be recovered from STAM-1 intact, demonstrating not only the interesting use of this MOF as a protecting group, but also the ability (for both STAM-1 and HKUST-1) to recover isotopically-enriched linkers, thereby reducing significantly the overall cost of the approach.PostprintPeer reviewe

Synthesis of 2-pyranosyl benzothiazoles, benzimidazoles and benzoxazoles via nucleophilic addition reactions of pyranosyl nitrile oxides

Reaction of per-O-acetylated-beta-D-pyranosyl nitrile oxides, generated by dehydrochlorination of the corresponding hydroximoyl chlorides, with 2-aminothiophenol afforded 2-(beta-D-pyranosyl)benzothiazoles. 1,2-Diaminobenzene and 2-aminophenol reacted similarly to yield 2-(beta-D-pyranosyl)benzimidazoles and 2-(beta-D-pyranosyl)benzoxazoles, respectively. The structures of 2-beta-D-glucopyranosylbenzimidazole (17), 2-(2,3,4-tri-O-acetyl-beta-D-xylopyranosyl)benzimidazole (19) and the xylopyranosyl thiohydroximate 13 were established by X-ray crystallography. (C) 2010 Elsevier Ltd. All rights reserved

Stereoselective synthesis of β-arabino glycosyl sulfones as potential inhibitors of mycobacterial cell wall biosynthesis

A series of β-arabino glycosyl sulfones with varying alkyl chain lengths were synthesised in a stereoselective fashion as putative mimics of decaprenolphosphoarabinose (DPA), and as potential inhibitors of mycobacterial cell wall biosynthesis. Biological testing against Mycobacterium bovis BCG revealed low to moderate anti-mycobacterial activity with marked dependence on alkyl chain length, which was maximal for a C-12 chain

9,14-diphenyl-9,9a,10,13,13a,14-hexahydro-9,14:10,13-dimethanobenzo[f]tetraphen-15-one

X-ray crystallography has been used to characterise the title compound for the first time, 1H NMR, 13C NMR and IR spectroscopic data has also been updated from earlier reports.Publisher PDFPeer reviewe

CCDC 2062443 & 2062444: Experimental Crystal Structure Determination

Related Article: Iain A. Smellie, Cameron L. Carpenter-Warren, Brian A. Chalmers, David B. Cordes, Rodrigo P. F. De A. Gouy, Neil S. Keddie, Tomas Lebl, Iain. L. J. Patterson, Alexandra M. Z. Slawin|2021|J.Chem.Educ.|98|3608|doi:10.1021/acs.jchemed.1c0051