Donor activity of cyclohexene and a series of n-alkanes in catalytic hydrogen transfer to various organic groups over magnesia as a catalyst has been determined. Styrene, phenylacetylene, benzaldehyde and acetophenone were not reduced by cyclohexene in the temperature range 523-673 K. Cyclohexene oxide was reduced to cyclohexanol (38%) and nitrobenzene to aniline (56%) by cyclohexene under adopted conditions (673 K). The highest yield of aniline (57%) from nitrobenzene was reached at 673 K in the presence of n-decane from a series Of C6 - C-16 n-alkanes used as hydrogen donors.