Acta Cryst. 1997, C53, in press (scheduled Dec. issue).
Exclusivity of the sp Rotamers of 9-(o-t-Butylphenyl)fluorene and 9-(o-t-Butylphenyl)-9-fluorenol in Solution and Crystalline State
PAUL D. ROBINSON,a YUQING HOU,b HISHAM G. LUTFIb AND CAL Y. MEYERSb
aDepartment of Geology, Southern Illinois University-Carbondale-4324, Carbondale, Illinois 62901, USA, bDepartment of Chemistry and Biochemistry, Southern Illinois University-Carbondale-4409, Carbondale, IL 62901, USA, E-mail: robinson@geo.siu.edu
Abstract
Both 9-(o-t-butylphenyl)fluorene (C23H22) and 9-(o-t-butylphenyl)-9-fluorenol (C23H22O) maintained sp rotameric structures exclusively in crystalline form as well as in solution. This result is in contrast to that obtained with the corresponding 9-(o-isopropylphenyl)fluorene and 9-(o-isopropylphenyl)-9-fluorenol. In-plane sterically imposed distortion of the t-butyl group is exhibited in sp-9-(o-t-butylphenyl)fluorene and to a much larger extent in sp-9-(o-t-butylphenyl)-9-fluorenol. The asymmetric unit of the latter contains two crystallographically distinct but nearly identical molecules which are hydrogen bonded to each other via their respective OH groups; hydrogen bonding between the crystallographically equivalent molecules is not observed.