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Electron-impact induced fragmentations of o-, m-, and p-hydroxyalkylphenones and their trimethylsilyl (TMS) ethers are studied by means of high-resolution mass spectrometry, metastable defocusing, and deuterium labeling of the TMS ether derivatives. A markedly increased methyl radical loss from the o-TMS ether is attributed to a proximity effect. Minor fragmentation was observed with m- and p-isomers. Significantly intense doubly-charged ions were formed from ketonic cleavage and by the loss of a TMS methyl radical. The sequence of fragmentation was found to depend on the size of the alkyl group attached to the ketone carbonyl.

Ion cyclotron resonance application to propanol ion structure formed in double McLafferty rearrangement, demonstrating direct enol ion formation instead of by isomerization or ketonization

Remote group interactions after electron impact in 4-substituted cyclohexanones, investigating mass spectrometry in structural and stereochemical problems

Computerized method of interpreting low resolution mass spectra in organic chemical analysis, describing inference maker program applications and results

Synthesized amino esters and ketones with varying distance between functionalities, examining mass spectral fragmentation

Discussion of the modification of the DENDRAL computer program to extend the program to cyclic structures which exceed numerically the linear molecules of a given composition. IR, NMR and mass spectroscopy is used to develop a method for identification of each of the 27 possible ketones (exclusive of 5 cyclopropanones) of composition C6H10O.

Electron impact promoted phenyl migration of trans phenyloctalone, considering mass spectrometry and stereochemistry

Mass spectral properties of alkoxycyclohexanol trimethylsilyl ethers and alkoxycyclohexyl trimethylsilanes, using deuterium labeling

Aliphatic ethers low resolution mass spectra interpretation using computer program heuristic DENDRAL

Isomeric 1-phenylheptenes mass spectra, investigating electron impact induced rearrangements of double bond

Electron impact induced fragmentation of androstane using deuterium labeling

Dialkyl ketone ion in double McLafferty rearrangement, applying ion cyclotron resonance to structural study

DENDRAL program used to construct all possible acyclic structural isomers of C, H, N and O

Ion structure of keto and enol and McLafferty rearrangements determined by ion cyclotron resonance spectroscopy

Mass spectra of 1,2-cyclohexane oxide and three deuterium labeled analogs

Cyclohexene oxide mass spectral fragmentation by means of deuterium labeled analogs

Evidence against electron impact induced alkyl shifts in mass spectra of alpha-hydroxy-ketones, showing thermal rearrangements

Mass spectra of 1,2-cyclohexanediol and deuterium labeled analogs data recorded and mechanistic rationalizations of degradation processes given

Electron impact induced fragmentation of ring D in steroids involving loss of carbon atoms analyzed by mass spectrometry

Xanthate and ester pyrolysis reactions in epimeric cis- and trans-2-methylcyclohexyl-S-methyl xanthates and acetates

Deuterium labeling techniques and high resolution mass spectrometry combined to study structural and stereochemical problems for S-methyl xanthates and esters

Mass spectra of isotopically labeled aliphatic ketones at low voltage, showing deuterium scrambling among alyphatic carbon atoms

Mass spectrometry in structural and stereochemical problems, discussing electron impact promoted fragmentation of substituted germacyclopentanes and germacyclopentenes

Putranjivadione established as new triterpene, noting structure

Mass spectrometry in structural and stereochemical problems, discussing ions origins in spectrum of alcyl n-hexyl cyanide

Mass spectra peaks of N-Acyl-2-indolinols fragmentation processes upon electron impact, noting compounds predominance in open chain tautomer gas phase

Mass spectrometry of cyclic sulfites and carbonate esters, analyzing electron impact induced fragmentations and metastable ion characteristics based on deuterium labeling

Alkyl group elimination in alpha-cleavage fragmentation processes of molecular ions of aliphatic ketones, Schiff bases and ethers at low ev

Organic mass spectrometry in structural and stereochemical problems, discussing competitive McLafferty rearrangements in bifunctional compounds

Cyclic ketones containing methoxyl and hydroxyl studied for oxygen rearrangement on electron impact

Pyrroles and related compounds, analyzing mass spectra and fragmentation of pyrromethanes, pyrromethenes, pyrroketones and pyrrolic analogues

Cyanohydrins and O-acylcyanohydrins fragmentation upon electron impact correlated with mass spectra molecular structure

Steroid trimethylsilyl ethers, analyzing peaks in mass spectra using deuterium labeling

Constitution of vallesiachotamine isolated from Peruvian Apocynaceae Vallesia dichotoma Ruiz et Pav

Mass spectrometry in structural and stereochemical problems of 16 Amaryllidaceae alkaloids

Stereospecificity in hydrogen transfer reaction characteristic of 6-keto steroids studied by mass spectrometry

Mass spectrometric fragmentation behavior of N-n- propyl and N-n-butyl pyrrolidone and N-alkyl succinimides subsequent to electron impact