Based on neighbouring group participation, we have proposed a bi-bridge reaction mechanism, i.e. in the path of the reaction, there is a bi-bridged structure with two bridging atoms across a single carbonus-cacbon bon...Based on neighbouring group participation, we have proposed a bi-bridge reaction mechanism, i.e. in the path of the reaction, there is a bi-bridged structure with two bridging atoms across a single carbonus-cacbon bond. We have studied it by ab initio molecular orbital calculation. And all the geometries of the bi-bridge structines studied by us are transition states of the bi-bridge reaction. The theoretical data of structures,energies, and charge distribution give good information about such kind of reactions.展开更多
A series of V-type chromophores with electron-rich heterocyclevinylene bridges have been synthesized via Wittig-Horner-Emmons and Vilsmeier reactions.All the target chromophores showed strong one-photon and two-photon...A series of V-type chromophores with electron-rich heterocyclevinylene bridges have been synthesized via Wittig-Horner-Emmons and Vilsmeier reactions.All the target chromophores showed strong one-photon and two-photon excited emission,and their electron properties could be tuned by using different heterocycles such as furan,thiophene and pyrrole moieties in I-III.The maximum two-photon absorption (TPA) cross sections occurred at 760 nm and were measured to be in the range of 400-800 GM.展开更多
文摘Based on neighbouring group participation, we have proposed a bi-bridge reaction mechanism, i.e. in the path of the reaction, there is a bi-bridged structure with two bridging atoms across a single carbonus-cacbon bond. We have studied it by ab initio molecular orbital calculation. And all the geometries of the bi-bridge structines studied by us are transition states of the bi-bridge reaction. The theoretical data of structures,energies, and charge distribution give good information about such kind of reactions.
基金the National Natural Science Foundation of China (21002075 and 21034006) for financial support
文摘A series of V-type chromophores with electron-rich heterocyclevinylene bridges have been synthesized via Wittig-Horner-Emmons and Vilsmeier reactions.All the target chromophores showed strong one-photon and two-photon excited emission,and their electron properties could be tuned by using different heterocycles such as furan,thiophene and pyrrole moieties in I-III.The maximum two-photon absorption (TPA) cross sections occurred at 760 nm and were measured to be in the range of 400-800 GM.
