1.The radical products of low-temperature reactions of hydrogen atoms with a number of derivatives of thiophene in the solid phase were studied.2.In the case of 2-methylthiophene, 2-thiophenealdehyde, and 2-acetothienone, H atoms are added to the ring at the C=C bonds, forming radicals with an unpaired electron on the carbon atom.3.In the interaction of 3-methylthiophene with H atoms, a 3-thienyl radical is formed as a result of stripping of a H atom from the CH3group.4.The reactions of H atoms with 2-chloro- and 2,5-dichlorothiophenes and complex carbonyl compounds and 2-nitrothiophene with AlCl3and H2SO4leads to radicals in which the unpaired electron is localized chiefly on the S atom.5.The radical products of gas phase reactions of H atoms at room temperature with 2-chloro-,2- and 3-methylthiophenes were studied. In the case of 2-chlorothiophene, the reaction leads to stripping of a Cl atom, while in the case of 2- and 3-methylthiophene it leads to stripping of a H atom from the CH3group.