T3P mediated intramolecular rearrangement of o-aminobenzamide to o-ureidobenzonitrile using isothiocyanates

SummaryThe thermo-oxidative decomposition of lovage (Levisticum officinale) and davana (Artemisia pallens) essential oils has been studied by pyrolysis-gas chromatography/mass spectrometry in 9% oxygen and 91% nitrogen atmosphere at 300 °C to simulate low-temperature tobacco heating conditions. Both lovage and davana oils contain numerous chemical substances; the main components of both oils are various oxygen-containing compounds. Isobenzofuranones are the most important constituents of lovage oil, and their relative intensity changed significantly during oxidative pyrolysis. (Z)-ligustilide underwent two kinds of decomposition reactions: an aromatization reaction resulting in the formation of butylidenephthalide and the scission of the lactone ring with the elimination of carbon dioxide or carbon monoxide. Davanone is the main component of davana oil, which did not decompose considerably during low-temperature oxidative pyrolysis. However, the relative yield of the second most intensive component, bicyclogermacrene, reduced markedly due to bond rearrangement reactions. Davana ether underwent oxidation reactions leading to the formation of various furanic compounds. The changes in the composition of both essential oils could be interpreted in terms of bond splitting, intramolecular rearrangement mechanisms and oxidation reactions of several constituents during low-temperature oxidative pyrolysis. The applied thermo-oxidative method was found to be suitable to study the stability of the essential oils and monitor the decomposition products under simulated tobacco heating conditions. In spite of the complicated composition of the essential oils, no evidence for interaction between the oil components was found. [Beitr. Tabakforsch. Int. 29 (2020) 27–43]

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ChemInform Abstract: STEREOCHEMICAL NONRIGIDITY IN SOLID ZIRCONIUM AND HAFNIUM TETRAKISTETRAHYDROBORATES. EVIDENCE FOR TWO DYNAMIC INTRAMOLECULAR REARRANGEMENT PROCESSES IN COVALENT TRIDENTATE TETRAHYDROBORATES

Chemischer Informationsdienst ◽

10.1002/chin.197808001 ◽

1978 ◽

Vol 9 (8) ◽

Author(s):

I.-S. CHUANG ◽

T. J. MARKS ◽

W. J. KENNELLY ◽

J. R. KOLB

Keyword(s):

Intramolecular Rearrangement ◽

Stereochemical Nonrigidity ◽

Rearrangement Processes

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Threonine 57 is required for the post-translational activation ofEscherichia coliaspartate α-decarboxylase

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s1399004713034275 ◽

2014 ◽

Vol 70 (4) ◽

pp. 1166-1172 ◽

Cited By ~ 5

Author(s):

Michael E. Webb ◽

Briony A. Yorke ◽

Tom Kershaw ◽

Sarah Lovelock ◽

Carina M. C. Lobley ◽

...

Keyword(s):

Crystal Structure ◽

Active Site ◽

Site Directed Mutagenesis ◽

Intramolecular Rearrangement ◽

Directed Mutagenesis ◽

Vitamin B ◽

Biosynthesis Pathway ◽

Serine Residue ◽

Translational Activation

Aspartate α-decarboxylase is a pyruvoyl-dependent decarboxylase required for the production of β-alanine in the bacterial pantothenate (vitamin B5) biosynthesis pathway. The pyruvoyl group is formedviathe intramolecular rearrangement of a serine residue to generate a backbone ester intermediate which is cleaved to generate an N-terminal pyruvoyl group. Site-directed mutagenesis of residues adjacent to the active site, including Tyr22, Thr57 and Tyr58, reveals that only mutation of Thr57 leads to changes in the degree of post-translational activation. The crystal structure of the site-directed mutant T57V is consistent with a non-rearranged backbone, supporting the hypothesis that Thr57 is required for the formation of the ester intermediate in activation.

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ChemInform Abstract: Photochemistry of the o-Nitrobenzyl System in Solution: Identification of the Biradical Intermediate in the Intramolecular Rearrangement

ChemInform ◽

10.1002/chin.199142093 ◽

2010 ◽

Vol 22 (42) ◽

pp. no-no

Author(s):

R. W. YIP ◽

Y. X. WEN ◽

D. GRAVEL ◽

R. GIASSON ◽

D. K. SHARMA

Keyword(s):

Intramolecular Rearrangement

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Intramolecular rearrangement of organosilyl groups between oxygen and nitrogen in aminosiloxanes: A joint experimental–theoretical study

Journal of Organometallic Chemistry ◽

10.1016/s0022-328x(03)00551-5 ◽

2003 ◽

Vol 686 (1-2) ◽

pp. 16-23 ◽

Cited By ~ 4

Author(s):

Susanne Kliem ◽

Uwe Klingebiel ◽

Stefan Schmatz

Keyword(s):

Theoretical Study ◽

Intramolecular Rearrangement

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Electrosynthesis of 1,4-bis(diphenylphosphanyl) tetrasulfide via sulfur radical addition as cathode material for rechargeable lithium battery

Nature Communications ◽

10.1038/s41467-021-23521-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Dan-Yang Wang ◽

Yubing Si ◽

Wei Guo ◽

Yongzhu Fu

Keyword(s):

Density Functional ◽

Chemical Space ◽

Functional Materials ◽

Radical Addition ◽

Chemical Diversity ◽

Energy Storage Materials ◽

Intramolecular Rearrangement ◽

Synthesis Methods ◽

Dithiophosphinic Acid ◽

Sulfur Radical

AbstractOrganic electrodes are promising as next generation energy storage materials originating from their enormous chemical diversity and electrochemical specificity. Although organic synthesis methods have been extended to a broad range, facile and selective methods are still needed to expose the corners of chemical space. Herein, we report the organopolysulfide, 1,4-bis(diphenylphosphanyl)tetrasulfide, which is synthesized by electrochemical oxidation of diphenyl dithiophosphinic acid featuring the cleavage of a P–S single bond and a sulfur radical addition reaction. Density functional theory proves that the external electric field triggers the intramolecular rearrangement of diphenyl dithiophosphinic acid through dehydrogenation and sulfur migration along the P–S bond axis. Impressively, the Li/bis(diphenylphosphanyl)tetrasulfide cell exhibits the high discharge voltage of 2.9 V and stable cycling performance of 500 cycles with the capacity retention of 74.8%. Detailed characterizations confirm the reversible lithiation/delithiation process. This work demonstrates that electrochemical synthesis offers the approach for the preparation of advanced functional materials.

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