Correlated Rotations in Benzylfluorene Derivatives: Structure, Conformation, and Stereodynamics.

CAN 148:426265 AN 2008:297535 CAPLUS (COPYRIGHT (C) 2008 ACS ON SCIFINDER (R)) ABSTRACT FLUORENE DERIVS., HAVING SUBSTITUTED BENZYL GROUPS BONDED TO POSITION 9, HAVE BEEN INVESTIGATED BY VARIABLE TEMP. NMR SPECTROSCOPY. STEREODYNAMIC PROCESSES INVOLVING RESTRICTED ROTATION ABOUT THE FLUORENYL-CH2 AND ARYL-CH2 BONDS HAVE BEEN OBSD., LEADING TO CONFORMERS AND ENANTIOMERIC FORMS, AND THE CORRESPONDING BARRIERS WERE DETD. BY LINE SHAPE SIMULATION. THESE DYNAMIC PROCESSES ARE INTERPRETED AS BEING DUE TO CORRELATED ROTATION PATHWAYS, ON THE BASIS OF DFT COMPUTATIONS THAT SATISFACTORILY REPRODUCE THE EXPTL. BARRIERS. THE STRUCTURES OF TWO SUCH COMPDS. WERE ALSO DETD. BY SINGLE-CRYSTAL X-RAY DIFFRACTION