Conserved hydrogen bonding in tetrahydrocarbazolone derivatives: influence of solution-state assembly on crystal form nucleation

Abstract

Two tetrahydocarbazolone derivatives were found to show multiple unsolvated crystal forms. A persistent dimer motif was detected in solution by FTIR spectroscopy that is maintained in the kinetic crystal forms. Rationally introduced steric bulk induces the formation of a more stable catemeric form.