Angewandte Chemie International Edition
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture (Angew. Chem. Int. Ed. 3/1998)
The cover picture shows the surface of the Ph3PC≡C molecule, calculated with the PM3 method and color-coded according to the molecular electrostatic potential (MEP). The color scale varies from −100 kcalmol−1 (blue) to +48 kcalmol−1 (red); interactions with the solvent were not taken into account. The strongly negative region at the Cβ atom, collinear with the C-C triple bond, is remarkable. More about the synthesis of this compound, which is isoelectronic to the isocyanides and for which no Lewis structure can be formulated that can correctly describe the geometry and charge distribution, as well as reactions and spectroscopic data is reported by H. J. Bestmann et al. on pages 338–342.