4-氧-3-氮杂-三环[5.3.1.0--(2,5)]十一烷-9-甲酸甲酯的合成及晶体结构
Synthesis and Crystal Structure of 4-Oxo-3-aza-tricyclo-[5.3.1.0--(2,5)]undecane-9-carb-oxylic Acid Methyl Ester
Abstract
以2-金刚烷酮为起始原料,通过烯烃与氯磺酰异氰酸酯的[2+2]环加成等5步反应合成了新型双环β-内酰胺类化合物5.采用1H nMr,Ir和MS等手段对所得化合物的结构进行了表征.此外,还通过将化合物5酰化并采用X射线单晶衍射分析方法进一步测定了化合物5的空间立体结构.结果表明,烯烃3与氯磺酰异氰酸酯的[2+2]环加成反应具有高度的立体选择性和区域选择性. Since the [2+2] cycloaddition of chlorosulfonyl isocyanate(CSI) with an alkene is a very effective method for the synthesis of β-lactams in organic synthesis.In this paper,a new type bicyclic β-lactam compound was synthesized starting from 2-adamantanone employing the [2+2]cycloaddition strategy.The compound 4-oxo-3-aza-tricyclo-[5.3.1.02,5]undecane-9-carb-oxylic acid methyl ester(5) was synthesized in five steps in 47.5% overall yield including esterification of the carboxy group,[2+2] cycloaddition of the alkene 3 with CSI.Their structures were characterized by means of 1H NMR,IR spectra and MS techniques,and the structure of 4-oxo-3-aza-tricyclo-[5.3.1.02,5]undecane-9-carb-oxylic acid methyl ester(5) was further determined by X-ray single crystal diffraction analysis method after the acylation reaction.The results indicate that the [2+2] cycloaddition of cyclic alkene 3 with chlorosulfonyl isocyanate proceeded with excellent regio-and stereo-selectivity.This work provides a good option for the chiral synthesis of β-lactams.