Packings zwitterionic bonded

Many solid-state reactions of all types rely on cleavage planes [1]. For example a-cinnamic acid 1 (Fig. 2.1.3) or anthracene 14 (Fig.2.1.13) with slightly inclined planar molecules in double or single layers are reactive in both solid-state photolysis and bromination [16]. The molecular packing of 35 is even more favorable for solid-state reactivity at its varied functionality (Fig. 2.1.21) as the molecules lie flat and as there is additional free space between the aromatic rings. The molecules 35 adopt the zwitterionic form with hydrogen bonds exclusively within the double layers. 

Fig. 6. Fragment of the crystal packing of the hydrated zwitterionic compound with refcode GAHFUS [126] showing the involvement of p (0)(0)]- units in N—H...O (blue dotted lines) and O—H...O (black dotted lines) hydrogen bonds, two symmetrically independent zwitterionic compounds in the structure are shown as blue and green apart the oxygen atoms of p (0)(0)]- units which are shown as red balls, the water molecules are represented with grey color. The cyclohexyl groups are shown as balls (green and blue).

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