作者:Daniele Giuffrida、Franz H. Kohnke、Melchiorre Parisi、Françisco M. Raymo、J.Fraser Stoddart
DOI:10.1016/s0040-4039(00)76982-6
日期:1994.7
4,5-Dimethylbenzo[1,2-c:3,4-c']difuran (7) is a highly reactive bisdiene, which undergoes Diels-Alder reactions with a wide variety of dienophiles, including dimethyl acetylenedicarboxylate and cis-1,4-dichlorobut-2-ene, to give phenanthrene derivatives, e.g. 10 and 12, respectively, following (hydrogenation and) dehydration of the bisadducts 8 and 11, respectively. 9,10-Dimethyl-1,4:5,8-diepoxy-1,4,5,8-tetrahydro-phenanthrene (5), as a result of thermal decomposition of either (i) its bisadduct 6 with tetraphenylcyclopenta-dienone or (ii) its hydrogenated derivative 14, is a very convenient precursor of 7.