Crystal Structures of Two Tetraalkylammonium Salts and One Dihydrate of 4,4'-Dihydroxybenzophenone

Two tetraalkylammonim salts and a dihydrate of 4,4'-dihydroxybenzophenone (DHBP) have been prepared and characterized by X-ray crystallography. In [(CH3)(4)N](C13H9O3) (1), the DHBP- anions pack to form two-dimensional puckered, hydrogen-bonded layers via O-H center dot center dot center dot O- hydrogen bonds between the hydroxyl groups. Comparatively, in [(C2H5)(4)N](2)(C13H8O3)center dot 10H(2)O, the DHBP2- anions act as proton acceptors to link ten water molecules generating two-dimensional planar hydrogen-bonded layers. The tetraalkylammonium cations are located between the hydrogen-bonded layers. Additionally, weak C-H center dot center dot center dot O hydrogen bonds between the anions and cations are present. The DHBP molecules in 3 ((C13H10O3)center dot 2H(2)O) are linked to the water molecules forming a three-dimensional hydrogen-bonded network by conventional O-H center dot center dot center dot O hydrogen bonding. Additionally, theoretical calculations were performed to explore the structural differences among the materials and the results were compared with the corresponding crystal structures. Two tetraalkylammonim salts and one dihydrate of 4,4'-dihydroxybenzophenone (DHBP) have been prepared and characterized by X-ray crystallography. The hydrogen bonding of the structures is presented.