The free-radical growth mechanisms for the formation of polycyclic arenes (PCAs) were constructed based on the block unit of benzene, and were calculated by the quantum chemistry PM3 method. Two kinds of reaction path...The free-radical growth mechanisms for the formation of polycyclic arenes (PCAs) were constructed based on the block unit of benzene, and were calculated by the quantum chemistry PM3 method. Two kinds of reaction paths are proposed and discussed. The calculation results show that the formation of PCAs is only controlled by the elimination of H atom from benzene, and the corresponding activation energy is 307.60 kJ·mol-1. H2 is only the ef-fluent gas in our proposed reaction mechanism, and the calculation results are in accord with the experimental facts.展开更多
Zigzag carbon nanobelts are a long-sought-after yet unrealized target for organic synthesis.Herein,we report a study toward the synthesis of tetrabenzo[10]cyclacene,an undocumented zigzag carbon nanobelt.The synthetic...Zigzag carbon nanobelts are a long-sought-after yet unrealized target for organic synthesis.Herein,we report a study toward the synthesis of tetrabenzo[10]cyclacene,an undocumented zigzag carbon nanobelt.The synthetic precursor of tetrabenzo[10]cyclacene is its box-shaped tetraepoxy derivative,which is synthesized through iterative Diels–Alder reactions utilizing a“C”-shaped building block.Attempted aromatization of this tetraepoxy nanobox toward the formation of a fully conjugated nanobelt results in an octahydro derivative of tetrabenzo[10]cyclacene.The structures of the tetraepoxy nanobox and octahydrotetrabenzo[10]cyclacene were both unambiguously identified with single-crystal X-ray crystallography.展开更多
基金Supported by the National Basic Research Program of China (2005CB221203)the National Natural Science Foundation of China (20576087, 20776093, 50534070)the Natural Science Foundation of Shanxi Province (2006011022, 2009021015)
文摘The free-radical growth mechanisms for the formation of polycyclic arenes (PCAs) were constructed based on the block unit of benzene, and were calculated by the quantum chemistry PM3 method. Two kinds of reaction paths are proposed and discussed. The calculation results show that the formation of PCAs is only controlled by the elimination of H atom from benzene, and the corresponding activation energy is 307.60 kJ·mol-1. H2 is only the ef-fluent gas in our proposed reaction mechanism, and the calculation results are in accord with the experimental facts.
基金This research was made possible as a result of generous grants from the Research Grants Council of Hong Kong(GRF 14300218)the Croucher Senior Research Fellowship.
文摘Zigzag carbon nanobelts are a long-sought-after yet unrealized target for organic synthesis.Herein,we report a study toward the synthesis of tetrabenzo[10]cyclacene,an undocumented zigzag carbon nanobelt.The synthetic precursor of tetrabenzo[10]cyclacene is its box-shaped tetraepoxy derivative,which is synthesized through iterative Diels–Alder reactions utilizing a“C”-shaped building block.Attempted aromatization of this tetraepoxy nanobox toward the formation of a fully conjugated nanobelt results in an octahydro derivative of tetrabenzo[10]cyclacene.The structures of the tetraepoxy nanobox and octahydrotetrabenzo[10]cyclacene were both unambiguously identified with single-crystal X-ray crystallography.
