Copper-containing catalytic slurries with different concentrations of active metal precursor solutions are synthesized by drop thermolysis in situ in the hydrocarbon medium of a slurry reactor. According to dynamic light scattering, the particle size of the catalytic slurry dispersion phase is 3-4.5 nm and it remains almost unchanged during the synthesis. Using FTIR spectroscopy it is shown that the structure of precursors of slurry active species depends on the concentration of solution, which may influence the phase composition of catalytically active fragments of the surface during the reduction and synthesis of alcohols. It is demonstrated that alcohols may be synthesized from CO and H(2)in the slurry reactor in the presence of the formed nanosized slurries. It is revealed that the composition of alcohol phase products differs significantly with target product selectivity being comparable: at a low concentration of precursor solution a marked amount of methanol is contained in the mixture (up to 66%), while an increase in the concentration of precursor solution causes a rise in the proportion of higher molecular weight alcohols to 88%.