A silicon(IV) corrole complex had not been isolated so far, although germanium(IV) or tin(IV) corrole complexes exist.

Takayuki Tanaka, Atsuhiro Osuka, Kyoto University, Japan, Dongho Kim, Yonsei University, Seoul, Republic of Korea, and colleagues have combined tetrachlorosilane as a silicon source with different substituted corroles in the presence of a base at 60 °C in dichloroethane. The purification of the products by silica-gel column chromatography afforded the first pure silicon(IV) corrole complexes (example pictured).

The complexes’ structures were confirmed by X-ray diffraction measurements. The central silicon atom has a square‐pyramidal coordination geometry, and thus, is situated out of the corrole plane.

The team also successfully synthesized a µ-oxo-bridged dimer of a silicon(IV) corrole by a reaction with methanesulfonyl chloride in pyridine at 100 °C. The synthesized complexes have interesting and potentially useful optical properties. According to the researchers, the results could lead to new pathways to functionalized corroles and to photophysical applications of corrole complexes.

• The First Silicon(IV) Corrole Complexes: Synthesis, Structures, Properties, and Formation of a μ-Oxo Dimer,
  Kento Ueta, Masaya Fukuda, Gakhyun Kim, Soji Shimizu, Takayuki Tanaka, Dongho Kim, Atsuhiro Osuka,
  Chem. Eur. J. 2018.
  https://doi.org/10.1002/chem.201800165