Pentagermapyramidane: Crystallizing the "Transition-State" Structure

• Published in: Angewandte Chemie (International ed.) Vol. 54; no. 19; pp. 5654 - 5657
• Main Authors: Lee, Vladimir Ya, Ito, Yuki, Gapurenko, Olga A., Sekiguchi, Akira, Minkin, Vladimir I., Minyaev, Ruslan M., Gornitzka, Heinz
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 04.05.2015; WILEY‐VCH Verlag; Wiley; Wiley Subscription Services, Inc; Wiley-VCH Verlag
• Edition: International ed. in English
• Subjects: Bonding; cage compounds; Chemical Sciences; Chemistry; Chemistry, Multidisciplinary; Computation; Coordination chemistry; Crystal structure; Crystallization; density functional calculations; Distortion; germanium; Minima; NMR spectroscopy; Physical Sciences; Potential energy; Pyramids; Science & Technology; Stability; X-ray diffraction; density functional calculations; CARBON; BOND COVALENT RADII; PYRAMIDANE; X-ray diffraction; BEARING; cage compounds; germanium; NMR spectroscopy; ELECTRON-DENSITY; X‐ray diffraction
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201500731

The first example of the homonuclear pyramidanes, pentagermapyramidane, was synthesized, fully characterized, and computationally studied to reveal its peculiar structural features and the nature of its apex‐to‐base bonding interactions. Both solid‐state and solution structures of pentagermapyramidane are discussed based on the computed stabilities of its square‐pyramidal and distorted forms. Germanium pyramids: The homonuclear pentagermapyramidane Ge[Ge4(SiMetBu2)4] (1) was synthesized and characterized. Crystal structures of two structural variations of 1 are reported: the distorted pyramidal structure 1 a, corresponding to the energy minima on the Ge5R4 potential energy surface (PES), and the square‐planar pyramidal 1 b, representing a transition state on the PES.