Resolution of (S,S)-4-(2,2,4-tri­methyl­chroman-4-yl)­phenyl camphanate and its 4-chromanyl epimer by crystallization

• Published in: Acta crystallographica. Section C, Crystal structure communications Crystal structure communications, 2005-01, Vol.61 (1), p.o32-o34
• Main Authors: Esterhuysen, Catharine, Bredenkamp, Martin W., Lloyd, Gareth O.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Crystalline state (including molecular motions in solids); Exact sciences and technology; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Theory of crystal structure, crystal symmetry; calculations and modeling
• ISSN: 0108-2701; 1600-5759
• DOI: 10.1107/S0108270104029671

Dianin's compound (4‐p‐hydroxy­phenyl‐2,2,4‐tri­methyl­chroman) has been resolved by crystallization of the (S)‐(−)‐camphanic esters (S,S)‐ and (R,S)‐4‐(2,2,4‐tri­methyl­chroman‐4‐yl)­phenyl 4,7,7‐tri­methyl‐3‐oxo‐2‐oxabi­cyclo[2.2.1]heptane‐1‐carboxyl­ate, both C28H32O5, from 2‐methoxy­ethanol, yielding the pure S,S diastereomer. The relative stereochemistry of both diastereomers has been determined by X‐ray crystallography, from which the absolute stereochemistry could be deduced from the known configuration of the camphanate moiety. The crystallographic conformations have been analysed, including the 1:1 disorder of the R,S diastereomer.