1379688-10-4Relevant academic research and scientific papers
Synthesis of oxorhenium acetyl and benzoyl complexes incorporating diamidopyridine ligands: Implications for the mechanism of CO insertion
Lilly, Cassandra P.,Boyle, Paul D.,Ison, Elon A.
experimental part, p. 4295 - 4301 (2012/08/08)
A series of oxorhenium alkyl, phenyl, and vinyl complexes of the form [(DAP)Re(O)(R)] (R = aryl, vinyl, alkyl) was reported, and their reactivity with CO was examined. The methyl complex 5a reacts with CO at a significantly faster rate (2.5 h) than the phenyl complex 7a (24 h). Computational (B3PW91) studies reveal that although the acyl complex is the least stable (ΔG 353 = -11.2 kcal/mol) with respect to CO insertion compared to the benzoyl complex (ΔG353 = -14.5 kcal/mol), the activation energy for CO insertion is lower for the methyl complex (ΔG ?353 = 14.6 kcal/mol) than for the phenyl complex (ΔG?353 = 17.4 kcal/mol). This is consistent with the previously proposed mechanism, where CO inserts directly into the Re-R bond without prior formation of a CO adduct. The X-ray crystal structures of complexes 6, 7a, 8a, and 9a are reported.
