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921.
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Giuseppe Bruno Francesco Nicol Archimede Rotondo Francesco Foti Francesco Risitano Giovanni Grassi 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(12):o879-o883
Conformational analyses and a structural comparison of the four spiro compounds 3‐bromo‐1,9‐diphenyl‐4‐p‐tolyl‐7‐oxa‐1,2,8‐triazaspiro[4.4]nona‐2,8‐dien‐6‐one, (I), C24H18BrN3O2, 3‐bromo‐4‐(4‐methoxyphenyl)‐1,9‐diphenyl‐7‐oxa‐1,2,8‐triazaspiro[4.4]nona‐2,8‐dien‐6‐one, (II), C24H18BrN3O3, 3‐bromo‐4‐(4‐chlorophenyl)‐1,7,9‐triphenyl‐1,2,7,8‐tetraazaspiro[4.4]nona‐2,8‐dien‐6‐one, (III), C29H20BrClN4O, and 3‐bromo‐1,7,9‐triphenyl‐4‐p‐tolyl‐1,2,7,8‐tetraazaspiro[4.4]nona‐2,8‐dien‐6‐one, (IV), C30H22.89Br1.11N4O, are presented. The molecular structures are rather similar, which is as expected since the compounds are all products of concerted 1,3‐dipolar attack on (Z)‐4‐arylidene oxazolone and pyrazolone derivatives. The observed conformations tend to favour extended π conjugation of the benzene rings and other π systems, as shown by a comparison of selected geometric parameters of the four structures. 相似文献
923.
Franco Montagna Martina Fedel Giuseppe Scianna 《International Journal of Approximate Reasoning》2013,54(5):573-589
The usual coherence criterion by de Finetti is extended both to many-valued events and to conditional probability. Special attention is paid to assessments in which the betting odds for conditioning events are zero. This case is treated by means of infinitesimal probabilities. We propose a rationality criterion, called stable coherence, which is stronger than coherence in the sense of no sure loss. 相似文献
924.
Giuseppe A. Consiglio Salvatore Failla Paolo Finocchiaro Kenneth I. Hardcastle 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):697-700
Williamson condensation of bis-o-hydroxy aryl phosphonates with dihaloalkylaryl derivatives yields the title compounds. They show interesting stereochemical aspects and some of them can be used in chiral recognitions and separations. 相似文献
925.
Marina Massaro Carmelo G. Colletti Bruno Fiore Valeria La Parola Giuseppe Lazzara Susanna Guernelli Nelsi Zaccheroni Serena Riela 《应用有机金属化学》2019,33(3)
A highly sustainable prototype of a flow system based on gold nanoparticles (4.2 nm) supported on thiol‐functionalized halloysite nanotubes (HNTs) was developed for catalytic applications. The catalytic performances were evaluated using the reduction of 4‐nitrophenol to 4‐aminophenol as a model system. Under the best experimental conditions (0.0001 mol%, 1.97 × 10?8 mg of Au nanoparticles), an impressive apparent turnover frequency value up to 2 204 530 h?1 was achieved and the halloysite‐based catalyst showed full recyclability even after ten cycles. The high catalytic activity confirms the importance of the use of HNTs as support for Au nanoparticles that can exert a synergistic effect both as medium for transfer of electrons from borohydride ions to 4‐nitrophenol and by modulating interfacial electron transfer dynamics. With the application of flow technology, the obtained heterogeneous HNT@Au catalyst was fully recovered and reused for at least one month. 相似文献
926.
Dr. Luis M. Mateo Luca Sagresti Dr. Yusen Luo Prof. Dirk M. Guldi Prof. Tomas Torres Dr. Giuseppe Brancato Dr. Giovanni Bottari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(64):16049-16055
Tetracyanobuta-1,3-diene (TCBD) is a powerful and versatile electron-acceptor moiety widely used for the preparation of electroactive conjugates. While many reports addressing its electron-accepting capability have appeared in the literature, significantly scarcer are those dealing with its chemical modification, a relevant topic which allows to broaden the chemical space of this interesting functional unit. Here, we report on the first example of a high-yielding cyano-Diels-Alder (CDA) reaction between TCBD, that is, where a nitrile group acts as a dienophile, and an anthryl moiety, that is, acting as a diene. The resulting anthryl-fused-TCBD derivative, which structure was unambiguously identified by X-ray diffraction, shows high thermal stability, remarkable electron-accepting capability, and interesting electronic ground- and excited-state features, as characterized by a thorough theoretical, electrochemical, and photophysical investigation. Moreover, a detailed kinetic analysis of the intramolecular CDA reaction transforming the anthryl-TCBD-based reactant into the anthryl-fused-TCBD product was carried out at different temperatures. 相似文献
927.
Giuseppe Ancona 《manuscripta mathematica》2015,146(3-4):307-328
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