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Published on: October 9, 2012
Hydroxy Mercapto Methylene: The Missing H2CSO Isomer
Markus Schauermann1, Peter R Schreiner1
1Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Abstract:
We report the isolation of hydroxy mercapto methylene (HO-C̈-SH) under cryogenic conditions via pyrolysis of 2-ethoxy-2-thioxo-acetic acid. The two most stable carbene rotamers form via extrusion of ethylene and CO2 from this precursor. This donor-stabilized carbene represents a hitherto uncharacterized CH2SO species and the first spectroscopically characterized free mercapto carbene. CCSD(T)/cc-pVTZ computations support our findings.
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