STUDIES ON CHEMISTRY OF HALOGENS AND OF POLYHALIDES .29. COMPLEX COMPOUNDS OF BROMINE CHLORIDE

Bromine chloride complexes with pyridine, 4-picoline, 2,3- 2,4-, 2,5-, 2,6-, 3,4-, and 3,5-lutidines, and 2,3,6-collidine were prepared. The lutidine complexes, except that of 3,4-lutidine, are quite stable at room temperature under anhydrous conditions. Formation constants of these complexes were determined in carbon tetrachloride solutions. Comparison of these values with the formation constants of iodine(I) chloride and iodine bromide shows that the order of the Lewis acid strength is ICl > IBr > BrCl. Far-infrared spectra of the complexes indicate that the fundamental Br-Cl vibration band is shifted from 430 to 280 cm-1 by complexation with pyridine. © 1969, American Chemical Society. All rights reserved.