FeCl3- and GaCl3-catalyzed dehydrative coupling reactions of chromone-derived Morita-Baylis-Hillman （MBH） alcohols with terminal alkynes were developed. The reactions provided exclusively a-regioselective and acetyl...FeCl3- and GaCl3-catalyzed dehydrative coupling reactions of chromone-derived Morita-Baylis-Hillman （MBH） alcohols with terminal alkynes were developed. The reactions provided exclusively a-regioselective and acetylene-substituted products in good yields.展开更多
The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated...The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated and it was pointed that the association entropy is driving force to form the ionic pair.展开更多
The mechanism of skeletal reorganization of1,6-enynes catalyzed by GaCl3 has been studied with the density functional method at the B3LYP/6-31G* level. Thestructures and energies of the stationary points were calcu-la...The mechanism of skeletal reorganization of1,6-enynes catalyzed by GaCl3 has been studied with the density functional method at the B3LYP/6-31G* level. Thestructures and energies of the stationary points were calcu-lated to identify the activation barriers. The transition states were testified with vibration analysis and IRC calculations. The results of calculation show that the conversion of 1,6-enynes is a step-wise reaction. The whole reaction process is formation and migration of three-membered cycle involving a three-center and two-electron (3c-2e) bond. High stereose-lectivity of the reaction is in good agreement with experi-mental results.展开更多
基金Project supported by the National Natural Science Foundation of China, Ministry of Science and Technology （973 Program, No. 2011CB808600） and the Chinese Academy of Sciences.
文摘FeCl3- and GaCl3-catalyzed dehydrative coupling reactions of chromone-derived Morita-Baylis-Hillman （MBH） alcohols with terminal alkynes were developed. The reactions provided exclusively a-regioselective and acetylene-substituted products in good yields.
文摘The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated and it was pointed that the association entropy is driving force to form the ionic pair.
文摘The mechanism of skeletal reorganization of1,6-enynes catalyzed by GaCl3 has been studied with the density functional method at the B3LYP/6-31G* level. Thestructures and energies of the stationary points were calcu-lated to identify the activation barriers. The transition states were testified with vibration analysis and IRC calculations. The results of calculation show that the conversion of 1,6-enynes is a step-wise reaction. The whole reaction process is formation and migration of three-membered cycle involving a three-center and two-electron (3c-2e) bond. High stereose-lectivity of the reaction is in good agreement with experi-mental results.
