Robert Boyle's chiral crystal chemistry: Computational re-evaluation of enantioselective adsorption on quartz

Bart Kahr, Brianne Chittenden, Andrew Rohl

Research output: Contribution to journalArticle

Abstract

While searching for early examples of interactions of organic chromophores with minerals in the context of a systematic study of the process of dyeing crystals, we came across Robert Boyle's description of an experiment that may have been evidence of the enantioselective adsorption of a natural product, carminic acid (7-β-D-glucopyranosyl-9,10-dihydro-3,5,6,8-tetrahydroxy-1- methyl-9,10-dioxo-2-anthracene-carboxylic acid), to the chiral surfaces of α-quartz, three centuries before such interactions became the subject of active chemical investigations. In order to determine whether Boyle did indeed observe enantioselective adsorption-albeit unbeknownst to him-we attempted to dye quartz with carminic acid according to his recipe. Quartz adsorbs carminic acid only because on heating it develops a network of microfissures that adsorb dye. This process depends on capillarity, not on specific non-covalent interactions; there is no evidence of enantioselectivity adsorption to heated crystals or enantioselective epitaxy to unheated crystals. These failures changed the focus of our inquiry: Why have almost all attempts to demonstrate the enantioselective adsorption of additives to quartz crystal surfaces been generally confounding and equivocal? In order to answer this question, we complement our experimental historical re-investigation with contemporary computational techniques for modeling crystal surface structure and the adsorption of additives. Minimizations of the energies associated with the adsorption of carminic acid to relaxed, hydrated d- and l-quartz {101̄0} surfaces are analyzed in light of quartz's abysmal record as an enantioselective stationary phase.

Original languageEnglish (US)
Pages (from-to)127-133
Number of pages7
JournalChirality
Volume18
Issue number2
DOIs
StatePublished - 2006

Keywords

  • Carminic acid
  • Cochineal
  • Enantioselective adsorption
  • Quartz
  • Robert Boyle

ASJC Scopus subject areas

  • Analytical Chemistry
  • Catalysis
  • Pharmacology
  • Drug Discovery
  • Spectroscopy
  • Organic Chemistry

Fingerprint Dive into the research topics of 'Robert Boyle's chiral crystal chemistry: Computational re-evaluation of enantioselective adsorption on quartz'. Together they form a unique fingerprint.

Cite this