Poly(1,4-butylene adipate) (1) was pyrolyzed in a porcelain boat placed in a quartz tube heated by a furnace. Volatile products were carried out of the heated zone into traps by a flow of nitrogen. Polyester 1 was pyrolyzed both near the entrance and near the exit of the heated zone, at 500 and 700 °C with and without a vacuum. Adipic acid (2), cyclopentanone (4), and a mixture of mono (5) and diesters (6) of the monomer, dimer, and trimer, were isolated as products of the pyrolyses.The pyrolyses of 1 at 500 °C near the exit of the heated zone at atmospheric pressure gave 14% of 2, 10% of 4, 40% of 5, and 18% of 6; 5 consisted of 26% monoester of monomer and 74% monoester of dimer, whereas 6 consisted of 63% diester of monomer and 37% diester of dimer. At 700 °C, 0.2–0.3 Torr, with 1 near the entrance of the heated zone, the yield of 2 was higher (∼35%), and trimers were found in the monoesters 5 and diesters 6, along with dimers and monomers.

An interesting rearrangement has been observed in the mass spectra of a series of N-benzoyl-2-hydroxyalkylamines. The hydrogen atom of the hydroxyl group is transferred to the N-benzoyl portion of the molecular ion and the bond between positions 1 and 2 in the N-alkyl group is cleaved. A rearrangement ion, observed at m/e 135, is formed along with a neutral aldehyde or ketone. When the hydroxylic hydrogen is replaced by a trimethylsilyl substituent, the latter group is transferred with comparable efficiency. Differences in the relative importance of this rearrangement in the mass spectra of a series of related compounds with decreasing substitution at position 2, have been explained by differences in the stabilities of the neutral molecules formed along with m/e 135 and by the occurrence of a double hydrogen rearrangement which competes if hydrogen atoms are present in a relationship gamma and delta to the carbonyl group.

Five children deficient in growth hormone were treated with oxandrolone and human growth hormone. Average nitrogen retained was calculated from nine day balance data. During some balance periods, nitrogen retention was calculated by determination of 15N labeled glycine, as reported in this article. Twenty milligrams of 15N in excess of the natural abundance was administered orally. Urines were collected prior to, as well as after, administration of glycine-15 N and were analyzed for 15N by mass spectrometry. The percentage of 15N ranged up to 0.449% for collection over a 24 hour period, compared with 0.364% from control samples without excess 15N. These 15N data, like those from nitrogen balance, show the stimulating effects of oxandrolone and human growth hormone in the group as a whole.

Results from the pyrolyses of 1-phenyl-2-benzothiazolinone (7) and 1-phenyl-2-benzothiazolinethione (8) are reported and compared with those obtained previously from the corresponding compounds without the N-phenyl group. The mass spectra of 7 and 8 are reported, also. The major fragmentation in the mass spectrum of 7 is the loss of CO, followed by loss of S or H. Pyrolysis of 7 at 750° in a stream of nitrogen gives phenothiazine (9, 31%) and carbazole (10, 28%), by loss of CO and of CO and S, respectively. Pyrolysis of 9 yields 10. The major fragmentation in the mass spectrum of 8 is the loss of H. Pyrolysis of 8 at 750° produces 2-(phenylthio)benzothiazole (11, 87%), which is an isomer of 8, resulting from phenyl migration, and 2-phenylbenzothiazole (12, 3%). Pyrolysis of 11 gives 12.

The mass spectra of 1-phenyl-2-benzimidazolinethione (3) and 1-phenyl-2-benzimidazolinone (4) have been compared with their pyrolysis products and similarities have been found. In the 70 eV mass spectrum of 3, the base peak results from the loss of H•; at low ionizing voltages, this path and a competing path, loss of S, are the only ones which remain. At 650° in a stream of N 2 , 1-phenylbenzimidazole (8, 20%) formed from the loss of S and benzimidazo-[2,1-b]benzothiazole (5, 11%) formed by loss of H 2 . The major fragmentation paths in the mass spectrum of 4 are loss of CHO• and NCO•. At 950°, phenazine (6, 35%) formed by loss of CH 2 O, and carbazole (7, 14%) formed by loss of HNCO. In each pyrolysis, 65–70% of the starting material was recovered or accounted for.

The high and low resolution mass spectra of the N-acetyl-N,O-methyl and N-acetyl-O-trimethylsilyl derivatives of kanamycin A have been determined and interpreted, along with those of deuterated analogs under conditions of electron impact. In addition, the chemical ionization mass spectrum of the N-acetyl-N,O-methyl derivative is presented. The use of these spectra for recognizing structural features, such as the sequence of the sugar units, is discussed. The characteristics of the two types of derivatives are compared. The value of the chemical ionization spectrum and the complementary nature of the data obtained from it are emphasized.

The electron-impact and chemical-ionization mass spectra of 2-benzoxazolinone (5), 2-benzimidazolinone (6), and 2-benzothiazolinone (7) have been compared with their pyrolysis products and parallels have been found. In each case, loss of CO occurs from [Formula: see text] followed by loss of CO for 5 and by HCN for 6 and 7. At 950° in a stream of N2, 5 gave 17% of C5H5N isomers, related to the loss of 2CO, along with 5.6% of quinoline. Compound 6 gave 14% of C6H4N2 isomers, related to the loss of CO. At 950°, 7 gave 2-thiophenecarbonitrile (1.1%), cyanonaphthalenes (4.5%), aniline (3%), cyanobenzene (2.5%), naphthalene (1.5%), and phenylisocyanate (2.5%). From 5–720–70% of the starting material was recovered or accounted for by isolation and identification of products in each case. G.c./m.s. was used to study pyrolysis mixtures.

AbstractDie Pyrolyse der 2‐Thione (I), (II) und (III) wird untersucht.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPyrolyses and mass spectra of the 2-thiones of benzothiazole, benzimidazole, and benzoxazoleD. C. DeJongh and M. L. ThomsonCite this: J. Org. Chem. 1973, 38, 7, 1356–1361Publication Date (Print):April 1, 1973Publication History Published online1 May 2002Published inissue 1 April 1973https://pubs.acs.org/doi/10.1021/jo00947a024https://doi.org/10.1021/jo00947a024research-articleACS PublicationsRequest reuse permissionsArticle Views118Altmetric-Citations17LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSemiempirical molecular orbital study of o-phenylene carbonate and o-phenylene sulfiteD. C. De Jongh and M. L. ThomsonCite this: J. Org. Chem. 1972, 37, 8, 1135–1137Publication Date (Print):April 1, 1972Publication History Published online1 May 2002Published inissue 1 April 1972https://pubs.acs.org/doi/10.1021/jo00973a013https://doi.org/10.1021/jo00973a013research-articleACS PublicationsRequest reuse permissionsArticle Views51Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMass spectra and pyrolyses of o-phenylene sulfite and related compoundsDon C. De Jongh and R. Y. Van FossenCite this: J. Org. Chem. 1972, 37, 8, 1129–1135Publication Date (Print):April 1, 1972Publication History Published online1 May 2002Published inissue 1 April 1972https://pubs.acs.org/doi/10.1021/jo00973a012https://doi.org/10.1021/jo00973a012research-articleACS PublicationsRequest reuse permissionsArticle Views231Altmetric-Citations27LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

AbstractFür das cyclische Carbonat (I) und die Sulfite (IV), (VII) u.a. werden die Pyrolyse und Massenspektren diskutiert und die erhaltenen Reaktionsprodukte er= örtert.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMass spectra and pyrolyses of tetrachloro-o-phenylene carbonate and tetrachloro-o-benzoquinoneDon C. DeJongh, David A. Brent, and R. Y. Van FossenCite this: J. Org. Chem. 1971, 36, 11, 1469–1474Publication Date (Print):June 1, 1971Publication History Published online1 May 2002Published inissue 1 June 1971https://pubs.acs.org/doi/10.1021/jo00810a006https://doi.org/10.1021/jo00810a006research-articleACS PublicationsRequest reuse permissionsArticle Views43Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

AbstractDie Massenspektren sowie die Pyrolyse von Tetrachlor‐o‐phenylen‐carbonat (I) und Tetrachlor‐o‐chinon (II) werden untersucht.

Generation of a σ,σ,π-triradical was attempted by collision-activated dissociation (CAD) of two iodine atoms and an NO· radical from 2,4-diiodo-5-nitroquinolinium cation in an ion trap mass spectrometer. However, the reactivity of the product was consistent with a monoradical rather than a triradical. The mechanism of its formation was explored. In the first CAD step, an iodine atom is lost to generate the 2-iodo-5-nitro-4-dehydroquinolinium cation. Quantum chemical calculations suggest that in the second CAD step, the radical site at C-4 adds to the adjacent NO2 group followed by loss of NO· to generate the 2-iodo-4-oxyl-5-dehydroquinolinium cation. Calculations also suggest that in the third CAD step, this cation cyclizes to form an oxygen-peri-bridged 2-iodoquinolinium cation that then loses the remaining iodine atom to generate a distonic 4,5-oxygen-peri-bridged 2-dehydroquinolinium cation. For the analogous 4-oxyl-5-dehydroquinolinium cation, the cyclization is calculated to be exoergic by 8.7 kcal mol–1, with a free energy barrier of 14.0 kcal mol–1. The cyclized product is the first experimentally observed oxygen-peri-bridged naphthalene derivative. It displays low reactivity. However, it's monoradical counterpart is highly reactive and undergoes typical radical reactions.

AbstractBei der Pyrolyse von o‐Phenylensulfit (I) entsteht unter Eliminierung von SO das Cyclopentadienon (II) als Zwischenstufe, es erfolgt sofortige Dimerisierung zu (III).

AbstractThe mass spectra of eleven diazoketones have been obtained. High resolution mass measurements of selected ions have shown initial loss of nitrogen followed by loss of carbon monoxide. In many of the spectra, flat‐topped metastables were observed.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMass Spectra and Pyrolyses of o-Phenylene Carbonate and Related CompoundsD DeJongh and D BrentCite this: J. Org. Chem. 1970, 35, 12, 4204–4208Publication Date (Print):December 1, 1970Publication History Published online13 August 2002Published inissue 1 December 1970https://pubs.acs.org/doi/10.1021/jo00837a610https://doi.org/10.1021/jo00837a610research-articleACS PublicationsRequest reuse permissionsArticle Views89Altmetric-Citations33LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts