e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
General Synthetic Entry to Linearly-Fused Dihydrobenzocyclobutene-1, 2-diones and Benzocyclobutene-1, 2-diones via Annulation of 1, 2-Bis (methylene) …
AH Schmidt, G Kircher, M Willems
Index: Schmidt, Arthur H.; Kircher, Gunnar; Willems, Markus Journal of Organic Chemistry, 2000 , vol. 65, # 8 p. 2379 - 2385
The tandem Diels-Alder/dehydrochlorination reaction of semisquaric chloride (1) with the 1, 2-bis (methylene) cycloalkanes 2a-c and 1, 2-bis (methylene)-4-cyclohexene (9) affords the linearly-fused cycloalkanodihydrobenzocyclobutene-1, 2-diones 3a-c and 3, 4, 7, 8- tetrahydrocyclobuta [b] naphthalene-1, 2-dione (10), respectively. On treatment with MnO2, 3a-c are dehydrogenated to the respective carbocycle-fused benzocyclobutene-1, 2- ...