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Reazioni di Diels-Alder ad alta pressione di dieni a struttura paraciclofanica. Applicazione alla sintesi di elicenofani
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A new mean of preventing salt crystallization damage to porous materials: crystallization inhibitor
No full textHigh-pressure Diels-Alder reaction. Preparation of [2.2]paracyclophane derivatives
No full textHigh-pressure Diels-Alder cycloaddition reactions of 5-ethenyl[2.2]indeno-paracyclophane with 1,4-benzoquinone, N-phenylmaleimide, and 2-inden-1-one have been studied. Attempts to convert the cycloadducts into the corresponding aromatic helicenophanes failed. All new compounds were characterized by extensive nuclear magnetic resonance (NMR) investigations
Synthesis of optically active polycyclic compounds by Diels-Alder reactions of (+)-nopadiene
No full textSynthesis of enantiopure angularly condensed [2.2]paracyclophanes containing five-membered rings
No full textOptically active angularly condensed [2.2]paracyclophanes containing five-membered rings have been synthesized by a two-step approach based on the Diels-Alder cycloaddition of (S)-(+)-4-vinyl[2.2]paracyclophane. Structural analysis by NMR spectroscopy is presented. These helicenophanes containing a cyclopentane ring show extraordinarily high specific rotations. This phenomenon has been discussed in terms of structural modifications caused by the replacement of the benzene unit with a cyclopentane ring. © 2003 Elsevier Science Ltd. All rights reserved
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