The first SiIV corrole complexes were synthesized in good yields by treatment of meso-triarylcorroles with tetrachlorosilane in 1,2-dichloroethane at 60 °C. The central silicon atom possesses a square-pyramidal coordination geometry with slightly longer Si−N bond lengths as compared with those of known triazacorrole SiIV complexes. The SiIV corrole complexes exhibit sharp and blue-shifted absorption spectra and larger fluorescence quantum yields as compared with the corresponding free-base corroles. A μ-oxo dimer of a SiIV corrole was synthesized upon treatment with methanesulfonyl chloride in pyridine at 100 °C. This dimer shows a face-to-face structure with a 90° twist in the solid state. Although the dimer exhibits a blue-shifted Soret band, reflecting the face-to-face geometry, it displays a largely red-shifted and broad fluorescence spectrum with a large Stokes shift, suggesting a large structural change in the S1 state. These intriguing optical properties have been comprehensively studied by magnetic circular dichroism (MCD) spectroscopy, femtosecond transient absorption (fs-TA) measurements, and theoretical calculations.
Bibliographical noteFunding Information:
The works at Kyoto and Kyushu were supported by a Grant-in-Aid from JSPS (Nos. JP25220822, JP26810021, JP16H00909, and JP17H05160). The work at Yonsei was supported by the Global Research Laboratory (GRL) Program funded by the Ministry of Science, ICT, & Future, Korea (2013K1A1A2A02050183).
All Science Journal Classification (ASJC) codes
- Organic Chemistry