Rates and mechanisms of the reactions of ethanol and propanol with fluorine and chlorine atoms

The reactions of C2H5OH (1), C2H5OD (2), C2D5OD (3), 1‐C3H7OH (4), 2‐C3H7OH (5), 2‐C3H7OD (6) with F atoms and the reactions of C2H5OH (7), 1‐C3H7OH (8), 1‐C3H7OD (9), 2‐C3H7OD (10) with Cl atoms have been studied in a discharge flow reactor and a Laval nozzle reactor at room temperature and at pressures of a few mbar. Samples of the reaction mixtures were withdrawn continuously by a molecular beam device and analyzed by a mass spectrometer. The rates of the reactions were measured relative to the standard reactions C2H6 + F (0) and C2H6 + Cl (00) yielding k1/k0 = 1.06, k2/k0 = 1.25, k3/k0 = 1.20, k4/k0 = 1.26, k5/k0 = 1.06, k6/k0 = 1.20, k7/k00 = 2, k9/k00 = 4. For the reactions of F atoms with alcohols the probability of attack at one of the alkyl H atoms was found to be five times less than at the hydroxyl H atom site. For the reactions of Cl atoms with alcohols no abstraction from the OH group was observed, the abstraction from the alkyl groups follows the thermodynamically favoured route by forming mainly secondary radicals.