The tetraene 7,7-dimethoxy-2,3,5,6-tetramethylenebicyclo[2.2.1]heptane is a key compound for the preparation of a large variety of acenes protected by a carbonyl bridge. We report here a medium scale preparation in seven steps of this valuable starting material. Diels-Alder addition between 6,6-dimethyl fulvene and maleic anhydride, followed by carboxylation, ozonolysis of the double bond, reduction
四烯 7,7-二甲氧基-2,3,5,6-四亚甲基双环 [2.2.1]
庚烷是制备由羰基桥保护的多种并苯的关键化合物。我们在这里报告了这种有价值的起始材料的七个步骤的中等规模制备。6,6-二甲基富烯和
马来酸酐之间进行狄尔斯-阿尔德加成,然后羧化,双键
臭氧分解,四个酯基还原,然后醇基
氯化和脱
氯化氢得到目标化合物,总产率为17%。