A unified synthesis of all stereoisomers of 2-(aminomethyl)cyclobutane-1-carboxylic acid
作者:Virginie André、Marjolaine Gras、Hawraà Awada、Régis Guillot、Sylvie Robin、David J. Aitken
DOI:10.1016/j.tet.2013.02.063
日期:2013.4
All four stereoisomers of 2-(aminomethyl)cyclobutane-1-carboxylic acid have been prepared starting from a single chirally derivatized unsaturated γ-lactam. A photochemical [2+2] cycloaddition reaction of this compound with ethylene was employed to create the four-membered ring exclusively with a cis ring configuration. The two diastereoisomers were separated conveniently by chromatography then the
2-(氨基甲基)环丁烷-1-羧酸的所有四种立体异构体都是从单个手性衍生的不饱和γ-内酰胺开始制备的。该化合物与乙烯的光化学[2 + 2]环加成反应被用于产生仅具有顺式环构型的四元环。两种非对映异构体可通过色谱法方便地分离,然后手性附肢被更方便的Boc保护基取代。碱介导的内酰胺水解提供了每个顺式靶结构作为单个对映体。将高效,串联的差向异构化/水解方案首次应用于每种顺式化合物的羧酰胺衍生物,以提供相应的反式化合物为单一异构体。