The hydrogen bond networks in nicinquinium salts

Crystals of nicinquinium chloride and bromide incorporate water molecules d ue to the imbalance of hydrogen bond donors and accepters. The resulting in termolecular hydrogen bond system indicates a better proton accepting abili ty of chloride ions than bromide ions. The chloride anions accept four hydr ogen bonds in an almost tetrahedral arrangement whereas only two are formed with the bromide anions. As a consequence in the crystal structure of the chloride a three dimensional network of hydrogen bonds is formed, while in that of the bromide only chains of hydrogen bonded species exist. Both cati ons retain the absolute configuration of all asymmetric carbon atoms as com pared with the absolute configuration of the parent cinchonine.