Über die Temperaturabhängigkeit der ¹³C‐NMR.‐Spektren von [5–6‐η‐(1Z, 5E)‐Cyclooctadien]tetracarbonyleisen und (1Z, 5E)‐Cyclooctadien

Abstract

On the Temperature Dependence of the 13C-NMR. Spectra of 15 -6-44 lZ, 5E)-Cyclooctadiene]tetracarbonyliron and of (lZ, 5E)-Cyclooctadiene SummaryThe activation parameters of the conformational ring inversion process (simultaneous rotation around the C (3), C (4) and C (7), C (8) bonds; cJ Scheme I) of the title compounds ( 1 and 2, respectively) have been determined between 275 K and 155 K by a complete line shape analysis of the temperature dependent proton noise-modulated decoupled I3C-NMR. spectra of 1 and 2. The temperature dependence of the rates ( k ( 1 ) and k(2), respectively) of the inversion process can be described by the following equations (no influence of the solvents was observed; Ea in J/mol): k ( l ) = 10'3,02*0,35 exp ( -(42010k 1470)/RT)sp' k ( 2 ) = 1013,05f0.17 exp ( -(33930 k 590)/RT) ') Teil der geplanten Dissertation, UniversitC de Fribourg. 58