Conformational investigation of two isomeric chiral porphyrins: a convergent approach with different techniques.
The conformation in solution of two atropisomeric meso-tetrabinaphthyl porphyrins, used as catalytic precursors in asymmetric synthesis, was studied by means of experimental ((1)H-NMR ROESY, UV-Vis, and circular dichroism) and computational (semiempirical structure optimization, DeVoe's coupled oscillators calculations) methods. UV-Vis and CD spectra are calculated for several molecular models, with a systematic sampling of the conformational space, and compared to the experimental ones, leading to a structural hypothesis which is confirmed by NMR and PM3.
di Bari
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Centro di Studio del CNR per le Macromolecole Stereordinate e Otticamente Attive, Dipartimento di Chimica e Chimica Industriale, Pisa, Italy.
Pescitelli
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Reginato
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Salvadori
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