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Methods for quantitatively determining reactive hydrogen in organic compounds have been reviewed to find the most suitable procedures for estimating the reactive structural units in coal degradation products. In the past, reaction with methylmagnesium iodide or lithium aluminum hydride has been used to determine total reactive hydrogen in organic compounds with an accuracy o f 1 3 to 5%. The types of compounds which have been determined are: alcohols, phenols, enols, mercaptans, acids. amines, amides, and water. Acylation methods. including acetylation, phthaloylation, benzoylation, ETHODS for quantitatively determiningreactive hydrogen in organic compounds-Le., hydrogen attached tonitrogen. oxygen, or sulfur and exceptionally reactive carbon-hydrogen structures-have been reviewed to find the most suitable procedures for estimating the reactive oxygen-and nitrogen-containing structures in coal degradation products. The chemical literature from 1927 to 1949, inclusive, has been thoroughly searched, and some earlier and more recent references have been consulted The literature previous to 1931 was reviewed by Meyer (93).Methyl Grignard reagents and lithium aluminum hydride will react quantitatively R ith reactive hydrogen atoms in organic compounds t o form methane and hydrogen, respectively. The gaa formed in each case is a memure of the "artive hydrogen." Other reagents have been reported for the determination of active hydrogen but are generally less satisfactory.Some of the active hydrogen atoms can also be replaced b i a(-yl groups, and compounds containing such hydrogen atoms are said to contain "acylatable hydrogen" or usually "acetylatable hydrogrn." ""wylatable hydrogen" and ' acetylatable hydrogen"are not strictly correct t e i m~, inaqmuch as the hydrogen is not acylated but rather replaced by an acyl group. However, these are convenient ternis which distinctly differentiate methods which involve acylation of reactive groups from the methods I T hich determine total "active hydrogen." Different reagents and conditions cause quantitative acylation of different functional groups, and consequently the terms "acylatable hydrogen" and "acetylatahle hydrogen" have little meaning unless the reagent and conditions are specified. Pa 1 Present addreas, Verona Research Center Koppers Co , Inc , Verona,formylation, and stearylation, vary greatly among themselves and give results depending on reagents and conditions. Variations of the most common method-i.e., acetylation using acetic anhydride and pyridine at approximately 100' C.-have been used to determine primary and secondary alcohols, "unhindered" phenols, and primary and secondary amines. Other acylation reagents may be advantageous if tertiary alcohols or pyrroles must be determined or selectivity of reaction is desired. Applicability of different acylation methods for determining functional groups has been tabulated.The methods of deterniining reactive hydrogen have thus been divided into two major groups-determinations of active hydrogrn and determinations o...
Methods for quantitatively determining reactive hydrogen in organic compounds have been reviewed to find the most suitable procedures for estimating the reactive structural units in coal degradation products. In the past, reaction with methylmagnesium iodide or lithium aluminum hydride has been used to determine total reactive hydrogen in organic compounds with an accuracy o f 1 3 to 5%. The types of compounds which have been determined are: alcohols, phenols, enols, mercaptans, acids. amines, amides, and water. Acylation methods. including acetylation, phthaloylation, benzoylation, ETHODS for quantitatively determiningreactive hydrogen in organic compounds-Le., hydrogen attached tonitrogen. oxygen, or sulfur and exceptionally reactive carbon-hydrogen structures-have been reviewed to find the most suitable procedures for estimating the reactive oxygen-and nitrogen-containing structures in coal degradation products. The chemical literature from 1927 to 1949, inclusive, has been thoroughly searched, and some earlier and more recent references have been consulted The literature previous to 1931 was reviewed by Meyer (93).Methyl Grignard reagents and lithium aluminum hydride will react quantitatively R ith reactive hydrogen atoms in organic compounds t o form methane and hydrogen, respectively. The gaa formed in each case is a memure of the "artive hydrogen." Other reagents have been reported for the determination of active hydrogen but are generally less satisfactory.Some of the active hydrogen atoms can also be replaced b i a(-yl groups, and compounds containing such hydrogen atoms are said to contain "acylatable hydrogen" or usually "acetylatable hydrogrn." ""wylatable hydrogen" and ' acetylatable hydrogen"are not strictly correct t e i m~, inaqmuch as the hydrogen is not acylated but rather replaced by an acyl group. However, these are convenient ternis which distinctly differentiate methods which involve acylation of reactive groups from the methods I T hich determine total "active hydrogen." Different reagents and conditions cause quantitative acylation of different functional groups, and consequently the terms "acylatable hydrogen" and "acetylatahle hydrogen" have little meaning unless the reagent and conditions are specified. Pa 1 Present addreas, Verona Research Center Koppers Co , Inc , Verona,formylation, and stearylation, vary greatly among themselves and give results depending on reagents and conditions. Variations of the most common method-i.e., acetylation using acetic anhydride and pyridine at approximately 100' C.-have been used to determine primary and secondary alcohols, "unhindered" phenols, and primary and secondary amines. Other acylation reagents may be advantageous if tertiary alcohols or pyrroles must be determined or selectivity of reaction is desired. Applicability of different acylation methods for determining functional groups has been tabulated.The methods of deterniining reactive hydrogen have thus been divided into two major groups-determinations of active hydrogrn and determinations o...
Schon immer besland das Bestreben, den Arbeiter der Blei verarbeitenden bzw. Bleisalze herstellenden lndustrien pgen die iiberaus gcfiihrlichen Bleivergiflungen zu schutzer Die gro6e Schildlichkeit des Bleistaubes wie der Bleiverbindungen far den menschlichen Organismus ist allgemein bekanht; sie soll daher im folgenden nur kurz geschildert werden. M e bftere Aufnahme kleiner Mengen von Bleisalzen per 08, das Emalmen bleihaltigen Slaubes, die wiederholle Resorption von Bleisubshzen durch die Haut und Haare verursachen chronische Bleivergiftungen, wie die sog. Mderkolik, Bleikolik, Lithargyrismus. Diese nehmen allerdings nur sellen eiaen lbdlichen Verlauf, machen aber den Kllrper siech und verkiinen das Leben. Allgemeine Anzeichen von chronischa Bleivergiftung sind bleiche Gesichtsfarbe, trockene Haul, Trockenheit im Munde, BleisaCm des Zahnfleisches, Verdauungsstbrungen, Ekel, Brechneigung, eingezogener Unterleib, erschwerter lrockener und liarler Stuhlgang, Schwinden der Kriifte, A n h i e , Kriimpfe, LHhnungen,, Abmagerung u. a. Erscheinungen. Bei geringerem Grade der Vergiftung kbnnen die einen oder anderen dieser Anreichen aber mehr oder weniger bzw. gar nicht vorhanden sein. Auch nach IPngerem Gebrauch von bleihaltigen UmschlHgen (z. B. von Bleiessig, Goulardischem Wasser) oder Einreibungen k6nnen diese Erscheinungen auftreten, die oft fur Rheuma, Gicht u. dgl. gehalten werden. Aus diesem Grunde sind auch bleihaltige Hamfirbemittel durehaur zu verwerfen und ihre Verwendimg und Herstellung in Deulschland mit Recht verboten.Es hat nicht an Verauchen gefehll, diesem Ubelsland abzuhelfen und gelangle schon vor Jahred eine angeblich Alhlipolysulllde enthaltende feste Natronseife unter der Bereichnung ,,A k r e m n i n -S e i f e" in den Handel. Diese sol1 beim Waschen Schwefelwasserstoff entwickeln und als Schutzmittel gegen Bleivergiftungen dienen, da der Schwefelwasrersloff jede geringsle. dem Kiirper etwa noch anhaflende Menge einer Bleiverbindung durch eine Dunkelflrbung der betreffenden Hautstellen deutlich anzeigt. Eine weilere Seife dieser A r t wurde unler dem Namen ,,Antib I e i s e i f e" in den Handel gebraclil. Diese stellt eine rnit Schwefelwassersloff gesPttigte flussige Kaliseife dal, welche Phnlich wie die . , A k r e m n i n -und E u s u l f i n s e i f e " von Bleiarbeilern benulzt werden soll.Ein Versuch, die oben erwiihnte ,,A k r e m n i n s e i f e" von verschiedenen einschliigigen Firmen zwecks Nachprurung der Reaktionsfiihigkeit dieser Seife auf Bleiverbim dungen zu bekommen, scheilerle, d a die angegebenen Hersteller dieser Seife nicht mehr existierten bzw. die Fabrikalion eingestellt hatten. Vielleicht war der Grund hierfur der. da6 diese Seife den an sie geslelllen Forderungeii nicht ganz entsprochen hat. Da nun Nachfragen nach einer Bleischutzseife immer wieder einlaufen, wurde versuchl. cine alkalipolysullldhaltige feste Seife dieser Art herzustellen. Zu diesem Zweck wurde einer Grundseife rnit einem Gehalt von etwa 0.10 v. H. an freiem Alkali 5 v. H. Schwefelleber, in m6glichst wenig...
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