B···π-aromatic and C–H···B interactions in co-crystals of aromatic amine N-oxides with p-phenylenediboronic acid

Co-crystals of p-phenylenediboronic acid with four aromatic N-oxides namely pyridine N-oxide, quinoline N, N′-dioxide, isoquinoline N, N′-dioxide and 4,4′-dipyridine N, N′-dioxide are prepared and are structurally characterized. The stacking pattern in each case is found to be different. An interesting stacking effect that, sandwiches the boronic acid groups by pyridine N-oxide rings and associated through η2 and η3 type B–π interactions is presented. In the structures of co-crystals of aromatic amine N-oxides with p-phenylenediboronic acid B···π aromatic and C–H···B interactions are observed.