Synthesis and Physical Properties of Sterically Congested Cycloalkenes, 1,2-Di-<i>tert</i>-butyl-3,3,5,5-tetramethylcyclopentene and 1,2-Di-<i>tert</i>-butyl-3,3,6,6-tetramethylcyclohexene
作者:Akihiko Ishii、Chie Tsuchiya、Takahiro Shimada、Ken Furusawa、Takenori Omata、Juzo Nakayama
DOI:10.1021/jo991760z
日期:2000.3.1
Two sterically congested cycloalkenes (9 and 10), congeners of tetra-tert-butylethylene, were synthesized and characterized. Oxidation of the bicyclic 1,3-dithietane 8 with dimethyldioxirane (DMD) gave the endo,endo-disulfoxide 13, thermal isomerization of which to the endo,exo-disulfoxide 15 followed by oxidation with DMD gave the trioxide 18. Heating 18 in refluxing 1,3-dimethyl-2-imidazolidinone
合成并表征了两个空间上拥挤的环烯烃(9和10),即四叔丁基乙烯的同类物。用二甲基二环氧乙烷(DMD)氧化双环1,3-二硫杂环丁烷8,得到内-内-二亚砜13,将其热异构化成内-外-二亚砜15,然后用DMD氧化,得到三氧化物18。加热回流18。 1,3-二甲基-2-咪唑啉酮通过2倍挤出工艺以69%的产率提供了1,2-二叔丁基-3,3,5,5-四甲基环戊烯(9)。1,6-二酮二hydr 23与Se(2)Cl(2)的反应得到硒代二唑啉34和1,3-二硒代烷35。在115-130摄氏度下加热34得到1,2-二叔-丁基-3,3,6,6-四甲基环己烯(10),四叔丁基乙烯的“二氢”衍生物,收率为43%。