The Reactions of NH(a1Δ) with Ethane, Propane, and Isobutane in the Liquid Phase

The photolysis of HN3 was studied in liquid ethane, propane, and isobutane at the temperature of Dry Ice–methanol. In the reaction mixtures, quaternary ammonium salts were formed between the basic products and HN3. The products were analyzed after having been passed through a trap containing NaOH, in which the salts were decomposed. The main products observed were nitrogen and amines: ethylamine from ethane, propyl– and isopropylamine from propane, and i-butyl, and t-butylamine from an isobutane solution. Ammonia and hydrogen were also formed as minor products. Possible reaction mechanisms are discussed. It is suggested that about 80% of the singlet NH is inserted into the C–H bond of paraffin to form amine and that 20% of it is deactivated to the ground triplet state by the reactions with paraffin. The relative efficiencies of the insertion into primary, secondary, and tertiary C–H bonds were estimated to be 1.0, 1.9, and 2.3 respectively.