Ethyl (3aR,7R,7aR)-2,2-dimethyl-7-((methylsulfonyl)oxy)-3a,6,7,7a-tetrahydrobenzo [d][1,3]dioxole-5-carboxylate is a key intermediate of oseltamivir, and its crystal structure and density functional theory (DFT) studies are conducive to exploring more reaction pathways for industrial applications. In this paper, the title compound was synthesized by esterification, condensation and sulfonylation from shikimic acid as the starting material. Its single crystal was obtained by solution crystallization and crystallographic analysis. The optimal structure and frontier orbital energies were calculated using the DFT in the B3LYP/6-311+G(2d, p) mode. The molecular structure optimized by DFT was compared with the crystal structure determined by X-ray single crystal diffraction, which provided similar results. The electrostatic formula and the frontier molecular orbitals of the molecule were further studied by using the DFT to reveal the physicochemical properties of the investigated compound.

乙基 ( 3aR,7R,7aR)-2,2-dimethyl-7-((methylsulfonyl)oxy)-3a,6,7,7a-tetrahydrobenzo [d][1,3]dioxole-5-carboxylate是奥司他韦的关键中间体，其晶体结构和密度泛函理论（DFT）研究有利于探索更多工业应用的反应途径。本论文以莽草酸为起始原料，经酯化、缩合、磺酰化反应合成了标题化合物。它的单晶是通过溶液结晶和晶体学分析得到的。使用 B3LYP/6-311+G(2d, p) 模式下的 DFT 计算最佳结构和前沿轨道能量。将 DFT 优化的分子结构与 X 射线单晶衍射确定的晶体结构进行比较，结果相似。