@article{oai:kutarr.kochi-tech.ac.jp:00000238,
 author = {ASAHARA, HARUYASU and KOIZUMI, TAKUYA and MOCHIZUKI, EIKO and OSHIMA, TAKUMI},
 issue = {Part. 3},
 journal = {Acta Crystallographica Section C},
 month = {},
 note = {The crystal structures of the thermally equilibrated two conformational isomers of the title epoxide, spiro[10,11-dihydro-5H-dibenzo[a,d]cycloheptene-5,8’-1’,5’-dimethyl-4’-oxa-tricyclo[5.1.0.0<^3’,5’>]octane-2’,6’-dione] (C_23H_<20>O_3), have been determined by X-ray diffraction. The tricyclicdione skeleton takes the anti-structure of oxirane and cyclopropane rings with respect to the conjunct quinone frame. The major isomer (IIb) has a fairly twisted boat form of the spiro-linked 10,11-dihydro-5H-dibenzo[a,d]cycloheptene ring folding opposite to the adjoining cyclopropane CH_3-substituent, whereas the minor isomer (IIa) has almost ideal twist-boat form of the seven-membered ring inversely folding to the side of relevant CH_3 group. The conformational structures of these isomers have been compared with those of the corresponding isomers of unepoxidized homobenzoquinone.},
 pages = {o136--o138},
 title = {Thermally Equilibrated Two Conformers of 10,11-Dihydro-5H-dibenzo[a,d]cycloheptene Spiro-linked Homobenzoquinone Epoxide},
 volume = {C62},
 year = {2006}
}