Halogen Bonding versus Hydrogen Bonding in Driving Self-Assembly Processes

Preferential intermolecular recognition is observed when copolymer 3 is formed from a solution containing 1, 2, and 4 (see scheme). This halogen-bonded copolymer is also obtained from crystallization of a mixture of 1 and 2. Thus halogen bonding can be more effective than hydrogen bonding, which is responsible for the formation of copolymer 5 from 1 and 4, in driving the self-assembly of organic derivatives.