**4. Conclusions**

In conclusion, we reported on the synthesis and characterization of a series of T8- and DDSQ-based double-decker silsesquioxanes bearing 4-substituted triazole ring with aryl, hetaryl, alkyl, silyl, and germyl groups via copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). From this group of compounds hetaryl-triazole i.e., pyridine- and thiophenylderivatives were selected and verified in terms of their coordinating properties towards Pd(II), Pt(II), and Rh(I) ions. As a result of performed tests, four types of complexes, i.e.,

two mononuclear iBuT8-based Pt- and Pd- with NˆN and NˆS ligands, dinuclear iBuT8- based Rh with NˆN ligand as well as DDSQ-based with two Pd ions coordinated with NˆN bidentate ligand were obtained and fully characterized. For the **DDSQ-2A1** ligand, this is the first example of using the pyridine-triazole moiety to anchor TM ion in the chemistry of DDSQ-compounds. These may be potentially valuable systems of catalytic activity that will be tested in our future studies.

**Supplementary Materials:** The following are available online, 1H, 13C, 29Si NMR spectra of all obtained compounds (Figures S1–S53).

**Author Contributions:** Designed and supervised, B.D.; Synthesis and characterization of the reported compounds, K.K., M.R., K.M., and J.D.; X-ray analysis and description M.K.; Writing—original draft preparation, M.R. and B.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by National Science Centre (Poland) Project OPUS UMO-2016/23/B/ST5/00201.

**Data Availability Statement:** The data presented in this study are available in this article or in a Supplementary Materials.

**Acknowledgments:** The authors are grateful to Rafał Januszewski for donation of iBu-SQ-Cl and to Jan Jarozek for the project of graphical abstract. ˙

**Conflicts of Interest:** The authors declare no conflict of interest.

**Sample Availability:** Not available.
