Rate Constants for Halogen Atom Transfer from Representative α-halocarbonyl Compounds to Primary Alkyl Radicals
Rate constants for halogen atom transfer from diethyl methyliodomalonate (7a), iodoacetonitrile (7b), ethyl 2-methyl-2-iodopropanoate (7c), ethyl iodoacetate (7d), diethyl methylbromomalonate (7e), and ethyl bromoacetate (7f) to simple primary alkyl radicals have been studied by a variety of competition reactions. The Arrhenius functions for halogen atom transfer to the undecyl radical from halides 7d and 7f are log (kI, M-1s-1) = 10.4 - 4.4/0 and log (KBr, M-1s-1) = 10.4 - 8.2/0, respectively. The rate constants for halogen atom transfer to a primary radical from the series of compounds 7a-f at 50 °C are 1.8 X 109, 1.7 X 109, ca. 6 X 108, 2.6 X 107, 1.0 X 106, and 7.0 X 104 M-1s-1, respectively. The kinetic values are useful for the planning of synthetic methods that incorporate an atom transfer-cyclization process.
Curran, Dennis P., Eric Bosch, Jere Kaplan, and Martin Newcomb. "Rate constants for halogen atom transfer from representative. alpha.-halo carbonyl compounds to primary alkyl radicals." The Journal of Organic Chemistry 54, no. 8 (1989): 1826-1831.
Journal of Organic Chemistry