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Frederick Kurzer Jayantilal N. Patel 《Monatshefte für Chemie / Chemical Monthly》1987,118(6-7):793-812
4,8-Dibromodiisophor-2(7)-en-l-ol-3-one is obtained by dibromination of the parent ketol, or by monobromination of the 4- or 8-bromo-analogues. It is converted, byKoch-Haaf carboxylation, into 4,8-dibromodiisophor-2(7)-en-3-one-1-carboxylic acid, which is also accessible by bromination of the appropriate preformed diisophorone-1-carboxylic acids. The existence of the dibromoketol in two stereoisomeric forms is traced to conformational differences of its 4-substituent.Acetolysis of the 4,8-dibromo-1-carboxylic acid or its methyl ester occurs exclusively at the 8-position, but hydrazinolysis removes both halogen substitutents, with formation of 4-hydrazono-diisophorones. The13C-nmr spectra reflect the structural and conformational changes. A general fragmentation pattern accounts for the behaviour of the individual compounds under electron impact.
Diisophoron und verwandte Verbindungen. 17. Mitt. Synthese und nucleophile Reaktionen von 4,8-Dibromdiisophoronen
Zusammenfassung 4,8-Dibromdiisophor-2(7)-en-l-ol-3-on wird durch Dibromierung des Stamm-Ketols oder durch Monobromierung seiner 4- oder 8-Monobrom-Derivate erhalten. MittelsKoch-Haaf Carboxylierung wird es in die entsprechende 1-Carbonsäure umgewandelt, die auch durch Bromierung von vorgebildeten Carbonsäuren zugänglich ist. Stereoisomere Formen des Dibromketols unterscheiden sich durch die Konformation ihres 4-Substituenten.Die Acetolyse der 4,8-Dibrom-1-carbonsäure beschränkt sich auf ihren 8-Substituenten; Hydrazinolyse entfernt hingegen beide Halogen-Atome unter Bildung von 4-Hydrazono-diisophoronen. Die13C-Kernresonanz-Spektren stimmen mit den Struktur- und Konfigurations-Änderungen überein. Das massenspektrometrische Verhalten der verschiedenen Verbindungen wird an Hand eines allgemeinen Fragmentations-Schemas erörtert.相似文献
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Ludwig Maier 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):5-15
Abstract Interaction of 4-phenoxy and 4-pyridyloxy substituted 1.2-dinitrobenzenes and aminoalkylphosphonates,-phosphinates, and -phosphine oxides produces mainly 5-phenoxy- and 5-pyridyloxy substituted 2-nitrophenylaminoalkyIphosphonates. -phosphinates and -phosphine oxides (Table I to IV and Figure 1 to 5). some of which show high herbicidal and plant growth regulating activity. The herbicidal activity increases from pyridyloxy-phenylaminoalkylphosphonates to phenoxy-phenylaminoalkyl-phosphonates, -phosphinates, -phosphine oxides. Of all the compounds tested the phosphine oxide 4a was at all concentrations the most active compound. 相似文献
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A. A. Semioshkin P. V. Petrovskii I. B. Sivaev E. G. Balandina V. I. Bregadze 《Russian Chemical Bulletin》1996,45(3):683-686
Tetrabutylammonium hydroxyundecahydro-closo-dodecaborate was obtained in high yield via [B12H11NMP]–(NMP =N-methylpyrrolidone) by the modified method. [Bi2H11OH]2– is easily acylated by aromatic acyl chlorides to give novel compounds [B12H11OCOAr]2– in high yields. All the compounds were characterized by standard and special NMR methods.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 722–725, March, 1996. 相似文献
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Dichloromethoxymethane reacts with the sodium salt ofcloso-dodecahydrododecaborate Na2B12H12 to give disubstituted cluster, which readily decomposes when treated with various reagents. This cluster reacts with water, forming the previously described 1,7-B12H10(OH)2
2–reaction with alcohols results in a novel 1,7-dialkoxy derivative, whereas interaction with morpholine in acetone solution affords the novel anion, 1-O-I-Pri-7-O(CH2CH2)N-B12H10
2–. All of these derivatives were isolated as cesium salts and characterized by one- and two-dimensional NMR techniques.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 421–424, March, 1995. 相似文献
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13C NMR spectra of a series of compounds obtained by alkylating 3,4-methylendioxyphenol with 1-bromo-3-methylbut-2-ene have been taken and the spectral peaks have been assigned. 相似文献
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Dihydroxycarbeniumhexafluorometallates – Synthesis, Spectroscopic Characterization, and Crystal Structure of HC(OH)2+AsF6? The preparation of HC(OH)2+ MF6? (M = As, Sb) by protonation of HCOOH in the superacid systems HF/MF5 is reported. The very hydrolysable and thermolabile salts are characterized by vibrational and NMR spectroscopic methods. Under inert conditions they are stable at ?40°C for some weeks. HC(OH)2+AsF6? crystallizes in the orthorhombic space group Pbca (No. 61) with a = 965.8(1), b = 1582.20(16), c = 766.40(8) pm with eight formula units per unit cell. 相似文献
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