A Forgotten Chiral Spiro Compound Revisited: 3, 3'‐Dimethyl‐3H, 3'H‐2, 2'‐spirobi[[1, 3]benzothiazole]. Issue 10 (25th August 2015)

• Record Type: Journal Article
• Authors: Lindamulage De Silva, Angélique; Risso, Vesna; Jean, Marion; Giorgi, Michel; Monnier, Valérie; Naubron, Jean‐Valère; Vanthuyne, Nicolas; Farran, Daniel; Roussel, Christian
• Is Part Of: Chirality. Volume 27:Issue 10(2015)
• Page Start: 716
• Page End: 721
• Publication Date: 2015-08-25
• Subjects: Chirality -- Periodicals; Pharmaceutical chemistry -- Periodicals; 541.22
• DOI: 10.1002/chir.22492
• Languages: English
• ISSNs: 0899-0042

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The title compound was obtained as a side product during dimerization‐oxidation steps of the carbene generated from <italic>N</italic>‐methylbenzothiazolium iodide. Chromatography on (<italic>S</italic>, <italic>S</italic>)‐Whelk O1 column showed on cooling a typical plateau shape chromatogram indicating an exchange between two enantiomers on the column. The thermal barrier to <named-content content-type="reactionType" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">racemization</named-content> was determined (85 kJ.mol<sup>−1</sup> at 10 °C) by dynamic high‐performance <named-content content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">liquid chromatography</named-content> (DHPLC).The absolute configuration of the first (<italic>M</italic>) and second eluted (<italic>P</italic>) enantiomers on the (<italic>S</italic>, <italic>S</italic>)‐Whelk O1 column was established by comparing the reconstructed circular dichroism (CD) spectra from the CD detector signal and the calculated CD spectrum of the (<italic>P</italic>) enantiomer. <named-content content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">Mass spectrometry</named-content> revealed that 3, 3'‐dimethyl‐3<italic>H</italic>, 3'<italic>H</italic>‐2, 2'‐spirobi[[1, 3]benzothiazole] can be viewed as a masked thiophenate attached to a benzothiazolium framework. <italic>Chirality 27:716–721, 2015</italic>. © 2015 Wiley Periodicals, Inc.</p> </abstract>