Structure of antischistosome compounds. IV. (3-Bromopropyl)triphenylphosphonium bromide.

C21H21BrP+.Br-, Mr = 464.2, monoclinic, P2(1)/c, a = 11.165(2), b = 10.160(2), c = 17.614(3)A, beta = 104.99(1) degree, V = 1930.08 A3, Z = 4, Dx = 1.597 g cm-3, graphite-monochromatized Cu K alpha radiation, lambda = 1.5418 A, mu = 61.6 cm-1, F(000) = 928, T = 292 K. Final R = 0.052 for 3255 observed reflections with I greater than 3 omega (I). Structure solved by direct methods. The bromopropyl moiety is in an extended conformation with the gauche+ C-C-C-Br torsion angle orienting the C-Br vector in a direction similar to the direction of the N-Br vector observed in the (2-aminoethyl)triphenylphosphonium bromide hydrobromide structure and the cyano vector in the (3-cyano-propyl)triphenylphosphonium bromide structure.