Amine groups planarity

Fig. 7.4. (Left) Schematic representation of the proposed TCDD recognition site showing the covalently derived amine groups at the edge of the cavity and the non-covalently positioned 7i-complexing comonomer residue co-planar with the ligand. (Right) Structures of aromatic comonomers used in this study pentafluorostyrene (8), l,4-bis-(3/4-vinylbenzoxy)-benzene (9) and l-methoxy-3,5-bis-(4-vinylbenzyloxy)-benzene (10). Adapted from [23].

The experimental geometry of formamide is practically planar, because of a certain amount of conjugation between the two groups, and therefore the properties of the aminic group in formamide should be different from those of a primary alifatic amine having a pyramidal NH2 group. 

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