Through a Glass Darkly—Some Thoughts on Symmetry and Chemistry

This article reviews the development of concepts of chirality in chemistry. The story follows the parallel development of the optical properties of materials and the understanding of chemical structure until the two are fused in the recognition of the tetrahedral carbon atom in 1874. The different types of chiral molecule that have been identified since the first concept of the asymmetric carbon atom are introduced as is the notation used in various disciplines of chemistry to describe the relative or absolute configuration. In the final section, a polemical case for a unified nomenclature is presented.

(Z)-1-Benzoyl-5-benzylidene-2-hydroxy-4-oxo-4,5-dihydro-1H-pyrrole-3-carbonitrile

The title compound, C19H12N2O3, obtained as an intermediate in the synthesis of a pyrrole derivative, is composed of a five-membered heterocycle with substituted groups via double or triple bonds as well as single bonds, without an asymmetric carbon atom. An intramolecular O—H...O link occurs. In the crystal, O—H...N hydrogen bonds link the molecules.

Bi-Functional Magnetical Chiral Ionic Liquids Derived from Imidazolium and Pyridinium

Novel Bi-Functional Magnetical Chiral Ionic Liquids (MCILs) Derived from Imidazolium and Pyridinium Were Synthesized via Simply Two Step Reactions. Optically Active Ionic Liquids Have an Asymmetric Carbon Atom Linked to the Positively Charged Imidazole Ring or Pyridine Ring, while the Magnetical Anion Contains Tetrachloroferrate (FeCl4-), their Properties of Chirality and Magnetism Were Characterized. the Structure of MCILs Would Promise a New Class of Bi-Functional Ionic Liquids.