Lessons on the Discovery and Assignment of Polymorphs, Highlighted by the Case of the Latent Pigment DPP-Boc

Research output: Contribution to journalArticle


  • EJ MacLean
  • BM Kariuki
  • JRA Cameron
  • MA Roberts
  • KDM Harris

Colleges, School and Institutes


The latent pigment 1,4-diketo-2,5-di-t-butoxycarbonyl-3,6-diphenylpyrrolo[3,4-c]pyrrole (DPP-Boc) has three well-characterized polymorphic forms (denoted alpha, beta, and gamma) in the solid state, although some confusion exists in the literature concerning the assignment of these polymorphs. This paper clarifies the assignment of the three polymorphs of DPP-Boc, discusses various issues concerning the polymorphism of this material, and highlights several general issues regarding the characterization, discovery, and assignment of polymorphic systems.


Original languageEnglish
Pages (from-to)853-857
Number of pages5
JournalCrystal Growth and Design
Issue number2
Publication statusPublished - 1 Feb 2009