The results of research in the field of preparation and application of di-n-alkyl- and di-n-hydroxyalkyl derivatives of cyclopentadiene are presented. The synthesis of these derivatives of cyclopentadiene was carried out on the basis of the reaction of alkylation of the latter with the corresponding aliphatic mono- and diatomic alcohols of the C-2-C-8 series in the presence of an alkaline catalyst modified with nanosized magnesium oxide. The physicochemical parameters were determined and the structures of the obtained compounds were determined by the NMR spectral method. The synthesized 1,3-di-n-alkylcyclopentadienes were subsequently hydrogenated in autoclave conditions and the corresponding di-n-alkylcyclopentanes were obtained. Their physical and chemical properties, as well as viscosity-temperature characteristics, have been determined. It was shown that the molar ratio of diene: alcohol affects the course of the reaction. With an increase in this ratio from 1:2 to 1:4, the yield of the target reaction product increases from 40% to 66.2%. The synthesized di-nalkylcyclopentanes have good viscosity indices and sufficiently low pour points, which creates the prerequisites for recommending their use as components of synthetic oils, since for synthetic oils the optimal viscosity index is considered to be above 150, and most often it is 160-180, and for of semi-synthetic and mineral oils, the viscosity index is 120-140 and 100, respectively. When determining the structures of di-n-alkylcyclopentadienes, it was found that the addition of alcohol molecules occurs in the 1,3-position. A probable mechanism of the reaction of cyclopentadiene alkylation with mono- and diatomic alcohols is proposed. As a result of the studies, it was found that the synthesized compounds have high viscosity indices and pour points (minus 55-60(0)C) and can be recommended as a component for synthetic oils