A convenient and efficient procedure for the synthesis ofN, N-bicyclic pyrazolidinone derivatives has been developed via the reaction of azomethine imines with terminal alkynes under the ball milling condition without...A convenient and efficient procedure for the synthesis ofN, N-bicyclic pyrazolidinone derivatives has been developed via the reaction of azomethine imines with terminal alkynes under the ball milling condition without sol- vent, which was promoted by calcium fluoride with a catalyst of copper（I） salt. The cyclization reactions exhibited moderate to high yields.展开更多
A fluorescent probe with a coumarin moiety bound to rhodamine 6G hydrazide（l） was synthesized. Its sensing behavior toward various metal ions was investigated with fluorescence methods. Compound I displays different...A fluorescent probe with a coumarin moiety bound to rhodamine 6G hydrazide（l） was synthesized. Its sensing behavior toward various metal ions was investigated with fluorescence methods. Compound I displays different fluorescence emission responses to Al^3＋ and Ca^2＋ at the same excitation wavelength in the visible light region, while no changes occur after the addition of other metal ions. The binding ratios of the complexs of 1-Al^3＋ and 1-Ca^2＋ are both 2：1 according to the Job plot and high resolution mass spectrometer（HRMS） experiments. Moreover, emission spectrum of 1-Ca^2＋ complex and absorption spectrum of the rbodamine dyes overlap largely. When Al^3＋ was added to the 1-Ca2＋ system, calcium in complex 1-Ca2＋ can be displaced by Al^3＋, resulting in the output of another ratiometric sensing signal, which demonstrates that the 1-Ca^2＋ complex can be served as a new and effective fluorescence resonance energy transfer（FRET） donor for rhodamine derivatives.展开更多
A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomat...A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.展开更多
基金Supported by the National Natural Science Foundation of China（Nos.21261008, 21471069）, the Special Integration Fund of Industry and Research of Hainan Province, China（No.CXY20130010）, the Natural Science Foundation of Hainan Province, China（No.213014） and the International Science and Technology Cooperation Projects of Hainan Province, China（No. KJI-IZ2014-05）.
文摘A convenient and efficient procedure for the synthesis ofN, N-bicyclic pyrazolidinone derivatives has been developed via the reaction of azomethine imines with terminal alkynes under the ball milling condition without sol- vent, which was promoted by calcium fluoride with a catalyst of copper（I） salt. The cyclization reactions exhibited moderate to high yields.
基金Supported by the National Natural Science Foundation of China（No.21261008）, the Key Scientific and Technological Plan Project of Hainan Province, China（No.ZDXM20110024）, the Hainan Province Special Integration Fund of Industry and Research, China（No.CXY20130010） and the International Science and Technology Cooperation Projects of Hainan Province, China（No. KJHZ2014-05）.
文摘A fluorescent probe with a coumarin moiety bound to rhodamine 6G hydrazide（l） was synthesized. Its sensing behavior toward various metal ions was investigated with fluorescence methods. Compound I displays different fluorescence emission responses to Al^3＋ and Ca^2＋ at the same excitation wavelength in the visible light region, while no changes occur after the addition of other metal ions. The binding ratios of the complexs of 1-Al^3＋ and 1-Ca^2＋ are both 2：1 according to the Job plot and high resolution mass spectrometer（HRMS） experiments. Moreover, emission spectrum of 1-Ca^2＋ complex and absorption spectrum of the rbodamine dyes overlap largely. When Al^3＋ was added to the 1-Ca2＋ system, calcium in complex 1-Ca2＋ can be displaced by Al^3＋, resulting in the output of another ratiometric sensing signal, which demonstrates that the 1-Ca^2＋ complex can be served as a new and effective fluorescence resonance energy transfer（FRET） donor for rhodamine derivatives.
基金support by Hainan Provincial Natural Science Foun-dation of China(220QN180,2019RC028,2019RC129,221QN173,221QN172)Hainan University Start-up Funds(KYQD(ZR)1854 and KYQD(ZR)1857)was appreciated.
文摘A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.
