Selective Reagent Ion Mass Spectrometric Investigations of the Nitroanilines

Catalytic deoxygenation of coal enhances the stability and combustion performance of coal-derived liquids. However, determination of the selectivity of removal of oxygen atoms incorporated in or residing outside of aromatic rings is challenging. This limits the ability to evaluate the success of catalytic deoxygenation processes. A mass spectrometric method, in-source collision-activated dissociation (ISCAD), combined with high resolution product ion detection, is demonstrated to allow the determination of whether the oxygen atoms in aromatic compounds reside outside of aromatic rings or are part of the aromatic system, because alkyl chains can be removed from aromatic cores via ISCAD. Application of this method for the analysis of a subbituminous coal treated using a supported catalyst revealed that the catalytic treatment reduced the number of oxygen-containing heteroaromatic rings but not the number of oxygen atoms residing outside the aromatic rings.<br>

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Tandem Mass Spectrometric Evaluation of Core Structures of Aromatic Compounds after Catalytic Deoxygenation

10.26434/chemrxiv.5410807 ◽

2017 ◽

Author(s):

Xueming Dong

Keyword(s):

Aromatic Compounds ◽

Supported Catalyst ◽

Mass Spectrometric ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Aromatic Rings ◽

Tandem Mass Spectrometric ◽

Catalytic Deoxygenation ◽

Oxygen Atoms

Catalytic deoxygenation of coal enhances the stability and combustion performance of coal-derived liquids. However, determination of the selectivity of removal of oxygen atoms incorporated in or residing outside of aromatic rings is challenging. This limits the ability to evaluate the success of catalytic deoxygenation processes. A mass spectrometric method, in-source collision-activated dissociation (ISCAD), combined with high resolution product ion detection, is demonstrated to allow the determination of whether the oxygen atoms in aromatic compounds reside outside of aromatic rings or are part of the aromatic system, because alkyl chains can be removed from aromatic cores via ISCAD. Application of this method for the analysis of a subbituminous coal treated using a supported catalyst revealed that the catalytic treatment reduced the number of oxygen-containing heteroaromatic rings but not the number of oxygen atoms residing outside the aromatic rings.<br>

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Confounding contaminants in mass spectrometric reaction monitoring

10.26434/chemrxiv.7488737.v1 ◽

2018 ◽

Author(s):

Gilian T. Thomas ◽

Landon MacGillivray ◽

Natalie L. Dean ◽

Rhonda L. Stoddard ◽

Lars Yunker ◽

...

Keyword(s):

Mass Spectrometry ◽

Mass Spectrometric ◽

Negative Ion ◽

Reaction Monitoring ◽

Schlenk Flask ◽

Dynamic Analyses ◽

Rubber Septa ◽

Negative Ion Mode ◽

Mode A

<p>Reactions carried out in the presence of rubber septa run the risk of additives being leached out by the solvent. Normally, such species are present at low enough levels that they do not interfere with the reaction significantly. However, when studying reactions using sensitive methods such as mass spectrometry, the appearance of even trace amounts of material can confuse dynamic analyses of reactions. A wide variety of additives are present in rubber along with the polymer: antioxidants, dyes, detergent, and vulcanization agents, and these are all especially problematic in negative ion mode. A redesigned Schlenk flask for pressurized sample infusion (PSI) is presented as a means of practically eliminating the presence of contaminants during reaction analyses.</p>

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Mass spectrometric study of the supramolecular structure of praseodymium tris-pivaloyltrifluoroacetonate

Журнал структурной химии ◽

10.26902/jsc20180809 ◽

2018 ◽

Vol 59 (8) ◽

Keyword(s):

Supramolecular Structure ◽

Mass Spectrometric Study ◽

Mass Spectrometric ◽

Spectrometric Study

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