A mechanism about the origin of the selectivities for the cleavage of dioxolane five-membered rings on pyranoside rings was suggested. Quantum chemical studies were performed to testify the rationality of the mechanis...A mechanism about the origin of the selectivities for the cleavage of dioxolane five-membered rings on pyranoside rings was suggested. Quantum chemical studies were performed to testify the rationality of the mechanism. It is thus suggested that the selectivities should be dependent on the differences of the free energy at the transition states when the five-membered ring cleaves. Natural bond orbital(NBO) analysis was further made to assess the influence of stereoelectronic effects on the selectivities.展开更多
基金Supported by the National Natural Science Foundation of China(No.20973077), the Program for New Century Excellent Talents in University of China(No.NCET-07-0358) and the Brain Gain Fund of Huazhong University of Science and Technology, China.
文摘A mechanism about the origin of the selectivities for the cleavage of dioxolane five-membered rings on pyranoside rings was suggested. Quantum chemical studies were performed to testify the rationality of the mechanism. It is thus suggested that the selectivities should be dependent on the differences of the free energy at the transition states when the five-membered ring cleaves. Natural bond orbital(NBO) analysis was further made to assess the influence of stereoelectronic effects on the selectivities.