The chiral title compound 5 has been synthesized by reductive coupling of 2,6,9-tri-tert-butyl-4-oxo-4,8-dihydrocyclohepta[def]defluorene (4). The free enthalpy of activation of the racemization of 5 was determined to 62.9 ± 0.8 kJ/mol by variable temperature NMR spectroscopy.
手性标题化合物5是通过2,6,9-三叔丁基-4-氧代-4,氧代-4,8-二氢环庚[def]
芴的还原偶联而合成的(4)。通过可变温度NMR光谱将5的消旋化的活化的自由焓确定为62.9±0.8kJ / mol。