170 research outputs found

    Logements : sommets atteints?.

    Get PDF
    Cette publication n'a pas de résumé

    First insights into the synthesis of carbo-phospholane and carbo-phospholene oxides

    Get PDF
    Fifteen-membered ring carbo-mers of five-membered rings are considered in the heterocyclic series of the phosphole oxide and less unsaturated parents. The synthesis of the first carbo-phospholane oxides is achieved by a [14+1] two-step/one-pot macrocyclization route with 86 % yield. Reduction of the latter phosphora-[5]pericyclyne with SnCl­2 allowed consistent 1H and 31P NMR characterization of the corresponding carbo-phospholene, produced with 11 % yield. The ultimate carbo-phosphole oxide could not be isolated, but preliminary results on alternative strategies towards this 14 pz-electron Hückel carbo-aromatic are reported.

    Towards fluorescent indolyl-carbo-benzenes

    Get PDF
    The C18 macro-aromatic carbo-benzene core is a strong chromophoric unit resembling the porphine ring which is prone to quench the emission of fluorophoric substituents. Within the aim of preparing fluorescent carbo-benzenes (and carbo-cyclohexadiene parents) for measurement of their two-photon absorption cross-section by the TPEF method, several indole derivatives were devised and anchored to the C18 macrocycle either directly, p-phenylogously or ethynylogously. Synthesis methodology and spectroscopical measurements are presented in a comparative prospec

    First example of ring carbomer of 1,4-cyclohexadiene

    Get PDF
    While a series of carbo-mers of 1,3-cyclohexadienes was reported through the use of a specifically developed synthetic strategy, no example of their 1,4-regioisomers was known. Inspired by the methodology elaborated for the preparation of the 1,3-isomers, the synthesis of the first example of carbo-mer of 1,4-cyclohexadiene is presented. Comparison of physico-chemical properties of this first representative with those of the recently described 1,4-regioisomer, especially UV-vis absorption properties, is also addressed
    • …
    corecore