Novel bifunctional five-membered cyclic dithiocarbonates (1,3-oxathiolane-2-thione)s were synthesized by the reactions of the corresponding bifunctional oxiranes (epoxides) with carbon disulfide at room temperature with lithium bromide as catalyst. Full characterization of these monomers was performed including elemental analysis, proton and carbon nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectroscopy, and Fourier transmission infrared (FTIR) spectroscopy. The polyaddition polymerization of 1,3-oxathiolane-2-thione with 1,4-diaminobutane at room temperature resulted in a poly(thiourethane) material. The latter undergoes crosslinking due probably to the autooxidation of the product and formation of disulfide linkages. The five-membered cyclic dithiocarbonate, 5-decyl-1,3-oxathiolane-2-thione, was used a model to demonstrate the usefulness of five-membered cyclic dithiocarbonates for the preparation of compounds bearing thiol and thiocarbamate groups. This functionality was desired for use as metallic nanoparticle stabilizers. A thermal decomposition oxidation method was used to synthesize the magnetic iron nanoparticles. The stabilized magnetic nanoparticles were characterized by transmission electron microscopy (TEM) to determine the shape and the size of the nanoparticles. Energy dispersive spectroscopy (EDS) was used to analyze the composition of the magnetic nanoparticles.