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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.
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2.
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   
3.
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   
4.
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   
5.
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   
6.
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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