Although naphthenes have long been identified as important feedstock components for the production of light olefins and aromatics in fluid catalytic cracking units,their cacking mechanism and microscopic reaction netw...Although naphthenes have long been identified as important feedstock components for the production of light olefins and aromatics in fluid catalytic cracking units,their cacking mechanism and microscopic reaction networks,such as activation modes,ring-opening paths,and the production of aromatics,remain debated.In this context,we reported experimental and computational work aimed at elucidating the reaction network of naphthenes in fluid catalytic cracking using cyclohexane as the model naphthene.First,the main reactions for the formation of highly selective and value-added products such as light olefins and aromatics were discussed.Then,the proportions of cyclohexane activation via(i)the non-classical carbonium mechanism and(ii)the classical carbenium mechanism were analyzed by data fitting methods,which revealed that around 32.6%of cyclohexane was initiated by path(i),and the remaining naphthene was activated by path(ii).Moreover,our DFT results showed that the ring opening of cyclohexane through pathway(i)was more difficult than that through path(ii),and ring opening followed by the ring contraction of cyclohexane carbenium ions was the most energetically favorable route among the different ring-opening ways.展开更多
A series of 2,2＇-dialkyl bis（3-methyl-6,7-dihydrobenzofuran-4（5H）-one） derivatives was prepared through H2SO4·SiO2 catalyzed condensation reaction under solvent-free conditions as potential anti-tumor agents...A series of 2,2＇-dialkyl bis（3-methyl-6,7-dihydrobenzofuran-4（5H）-one） derivatives was prepared through H2SO4·SiO2 catalyzed condensation reaction under solvent-free conditions as potential anti-tumor agents. All of them were characterized by ESI-MS, IR and NMR spectra. Meanwhile, the single crystal of the target compound （4b）, C24H28O4, was also obtained and determined by X-ray crystallography. Crystal data： triclinic system, space group P , a = 8.463（10）, b = 9.612（11）, c = 13.828（15） , α = 74.29（5）, β = 80.93（5）, γ = 69.90（3）°, V = 1014（2） 3, Z = 2, F（000） = 408, Dc = 1.246 g/cm3, μ = 0.084 mm？1, R = 0.0883 and wR = 0.2440 for 4616 independent reflections （Rint = 0.1200） and 3490 observed ones （I 〉 2σ（I））.展开更多
基金This work was performed with the financial support of Sinopec Research Institute of Petroleum Processing(RIPP,Proj.R17022).
文摘Although naphthenes have long been identified as important feedstock components for the production of light olefins and aromatics in fluid catalytic cracking units,their cacking mechanism and microscopic reaction networks,such as activation modes,ring-opening paths,and the production of aromatics,remain debated.In this context,we reported experimental and computational work aimed at elucidating the reaction network of naphthenes in fluid catalytic cracking using cyclohexane as the model naphthene.First,the main reactions for the formation of highly selective and value-added products such as light olefins and aromatics were discussed.Then,the proportions of cyclohexane activation via(i)the non-classical carbonium mechanism and(ii)the classical carbenium mechanism were analyzed by data fitting methods,which revealed that around 32.6%of cyclohexane was initiated by path(i),and the remaining naphthene was activated by path(ii).Moreover,our DFT results showed that the ring opening of cyclohexane through pathway(i)was more difficult than that through path(ii),and ring opening followed by the ring contraction of cyclohexane carbenium ions was the most energetically favorable route among the different ring-opening ways.
基金supported by the National Natural Science Foundation of China(No.21602123)China Scholarship Council(No.201508420062)Youth Talent Development Foundation of China Three Gorges University
文摘A series of 2,2＇-dialkyl bis（3-methyl-6,7-dihydrobenzofuran-4（5H）-one） derivatives was prepared through H2SO4·SiO2 catalyzed condensation reaction under solvent-free conditions as potential anti-tumor agents. All of them were characterized by ESI-MS, IR and NMR spectra. Meanwhile, the single crystal of the target compound （4b）, C24H28O4, was also obtained and determined by X-ray crystallography. Crystal data： triclinic system, space group P , a = 8.463（10）, b = 9.612（11）, c = 13.828（15） , α = 74.29（5）, β = 80.93（5）, γ = 69.90（3）°, V = 1014（2） 3, Z = 2, F（000） = 408, Dc = 1.246 g/cm3, μ = 0.084 mm？1, R = 0.0883 and wR = 0.2440 for 4616 independent reflections （Rint = 0.1200） and 3490 observed ones （I 〉 2σ（I））.
