The rational chemical modification of carbon nanotubes (CNT) is crucial for their successful application in various areas of science and industry. In our approach, Birch reduction of single-walled carbon nanotubes (SWCNT) was followed by epoxidation with dimethyldioxirane (DMDO). Next, ring-opening reactions with thiosemicarbazide, p-phenylenediamine, aminosilica-coated magnetic nanoparticles, propargyl alcohol, 6-bromohexanoic acid, and ethyl potassium dithiocarbonate were performed, which resulted in a wide variety of functional groups being covalently anchored to the sidewalls of the nanotubes. Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible-near infrared spectroscopy (UV-Vis-NIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) were employed to confirm modifications and study the chemical composition of the obtained structures.