Self‐Complementarity Achieved through Quadruple Hydrogen Bonding

Highly stable dimers are formed in solution and in the solid state by a class of readily synthesized, self-complementary building blocks for supramolecular chemistry, which associate through a donor-acceptor-donor-acceptor array of four hydrogen-bonding sites. An additional intramolecular hydrogen bond in the compound whose crystal structure is shown on the right preorganizes the molecule for dimerization.