Stable carbonium ions. LXVII. Halonium ion formation via 1,4-halogen participation. Five-membered-ring tetramethylenehalonium, 2-methyltetramethylenehalonium, and 2,5-dimethyltetramethylenehalonium ions was written by Olah, George A.;Peterson, Paul E.. And the article was included in Journal of the American Chemical Society in 1968.Electric Literature of C5H11BrO This article mentions the following:
Tetramethylene-and 2-methyltetramethylenechloronium, -brominium, and -iodonium ions were formed by ionization of 1,4-dihalobutanes and 1,4-dihalopentanes, resp., in SbF5-SO2 solution at -60°. 2,5-Dimethyltetramethylenehalonium ions were formed by protonation of 5-halo-1-hexenes in fluorosulfonic acid-antimony pentafluoride-sulfur dioxide. Selected five-membered-ring halonium ions were shown by N.M.R. observation to be stable for brief periods of time even at temperatures in the range -30 to 0°, depending on the structure. In the experiment, the researchers used many compounds, for example, 1-Bromo-4-methoxybutane (cas: 4457-67-4Electric Literature of C5H11BrO).
1-Bromo-4-methoxybutane (cas: 4457-67-4) belongs to organobromine compounds. Bromo compounds are employed in a variety of metal-catalyzed coupling reactions. They are also ideal candidates for the synthesis of Grignard reagents that have wide-applicability in organic synthesis. alpha-Bromoesters are employed in the Reformatsky reaction for the synthesis of beta-hydroxyesters. Commercially available organobromine pharmaceuticals include the vasodilator nicergoline, the sedative brotizolam, the anticancer agent pipobroman, and the antiseptic merbromin. Electric Literature of C5H11BrO
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary