Chemometric analysis of skeletal data from non-fused and non-pi-complexed pentafulvenes

A broad chemometric study was made on structural data from non-fused and no n-pi-complexed pentafulvenes obtained both from the Cambridge structural da tabase (CSD) and from several studies to synthesise new fulvene compounds. Three main differentiated pentafulvene groups can be established considerin g bond distances extracted from the CSD database. Structural data for the n ew I-mono and 1,4-disubstituted 2,3,6-trioxypentafulvenes and 1,4-disubstit uted-6-amino-2, 3-dioxypentafulvenes reveal different structural behaviours due to their high functionality. The chemometric techniques employed compr ise principal component analysis, cluster analysis, selection of essential variables (Procrustes rotation) and isoprobability curves, all of them givi ng essentially the same general chemical conclusions. (C) 1999 Published by Elsevier Science B.V. All rights reserved.