The rotational barrier of chiral 2-carboxy-2'-methoxy-6-nitrobiphenyl has been evaluated both by density functional calculations. at the B3LYP/6-31G(d) and B3LYP/6-311+G(d,p) levels of theory, and by HF and post HF MP2 calculations at the 6-31G(d) level of theory. The DFT computed data, which seemed almost independent of the basis set used, are in good agreement with the values obtained from dynamic HPLC enantiomerization experiments and from the racemization rate constant of one of the enantiomers obtained by CD. The HF model seems to overestimate the barrier whereas the MP2 calculations confirm the DFT results. (C) 2003 Elsevier Ltd. All rights reserved.
Determination of the rotational barrier of a chiral biphenyl: Comparison of theoretical and experimental data / Ceccacci, Francesca; Giovanna, Mancini; Mencarelli, Paolo; Villani, Claudio. - In: TETRAHEDRON-ASYMMETRY. - ISSN 0957-4166. - STAMPA. - 14:20(2003), pp. 3117-3122. [10.1016/s0957-4166(03)00544-5]
Determination of the rotational barrier of a chiral biphenyl: Comparison of theoretical and experimental data
CECCACCI, FRANCESCA;MENCARELLI, Paolo;VILLANI, Claudio
2003
Abstract
The rotational barrier of chiral 2-carboxy-2'-methoxy-6-nitrobiphenyl has been evaluated both by density functional calculations. at the B3LYP/6-31G(d) and B3LYP/6-311+G(d,p) levels of theory, and by HF and post HF MP2 calculations at the 6-31G(d) level of theory. The DFT computed data, which seemed almost independent of the basis set used, are in good agreement with the values obtained from dynamic HPLC enantiomerization experiments and from the racemization rate constant of one of the enantiomers obtained by CD. The HF model seems to overestimate the barrier whereas the MP2 calculations confirm the DFT results. (C) 2003 Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.