3,3',5,5'-Tetrabromophenolsulfonphthalein (bromphenol blue),* C₁₉H₁₀Br₄O₅S

Abstract

M_r=670.02, monoclinic, C2/c, a= 31.003(4), b=11.037(2), c=21.183(3)Å , β = 143.7 (1) ° , V= 4291.2Å ³, D,_m = 2.06, D _x = 2.07Mgm ^-3, Z=8, MoKa, λ=0.7107 Å , μ =7.45 mm^-1, F(000) = 2560, T= 293 K, R = 0.061 for 1697 observed reflections. The bromphenol blue molecule consists essentially of three planar groupings: the sulfonphthalein ring system and two dibromophenol rings attached to the tetrahedral C atom of the five-membered ring of the sulfonphthalein system. The dibromophenol rings are inclined with resPect to each other at 73 ° whereas they make angles of 85 and 68 ° with respect to the sulfonphthalein system. The molecules aggregate into helical columns with the non-polar regions of the molecules in the interior and the polar regions on the surface. The columns are held together by a network of hydrogen bonds.