Details

Autor(en) / Beteiligte

• Cotton, F Albert
• Murillo, Carlos A
• Yu, Rongmin

Titel

Dynamic equilibrium between cyclic oligomers. Thermodynamic and structural characterization of a square and a triangle

Ist Teil von

• Dalton transactions : an international journal of inorganic chemistry, 2006-01 (32), p.3900-3905

Ort / Verlag

England

Erscheinungsjahr

2006

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A dynamic equilibrium has been found in CDCl3 between a neutral molecular square, [cis-Mo2(DAniF)2]4(O2CC6F4CO2)4 (1) and triangle, [cis-Mo2(DAniF)2]3(O2CC6F4CO2)3 (2) (DAniF = the anion of N,N'-di-p-anisylformamidine). The two components have been crystallographically characterized and solution studies by 1H and 19F NMR spectra of the concentration- and the temperature-dependence of the equilibrium have been performed. The conversion of three moles of molecular squares 1 to four moles of molecular triangles 2 has an equilibrium constant of 1.98(7) x 10(-4) at 23.7 degrees C. At this temperature, the DeltaG(0) for the conversion of three moles of squares to four moles of triangles is 21.0 kJ mol(-1). The conversion is enthalpically disfavored (DeltaH(0) = 23.5 kJ mol(-1)), but entropically favored (DeltaS(0) = 8.2 J K(-1) mol(-1)).