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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.
The Journal of Physical Chemistry Letters
|March 31, 2022
Summary
Researchers isolated hydroxy mercapto methylene, a novel sulfur-containing carbene species (CH2SO), under cryogenic conditions. This groundbreaking discovery provides the first spectroscopic characterization of a free mercapto carbene.
Area of Science:
- Organic Chemistry
- Spectroscopy
- Computational Chemistry
Background:
- Carbenes are reactive intermediates crucial in organic synthesis.
- Characterization of novel carbene species expands fundamental chemical knowledge.
- Sulfur-containing organic molecules present unique chemical properties.
Purpose of the Study:
- To isolate and characterize a novel mercapto carbene species.
- To investigate the formation pathways of this new chemical entity.
- To provide spectroscopic evidence for the existence of CH2SO.
Main Methods:
- Pyrolysis of 2-ethoxy-2-thioxo-acetic acid under cryogenic conditions.
- Spectroscopic analysis to identify the isolated species.
- High-level computational chemistry (CCSD(T)/cc-pVTZ) for theoretical support.
Main Results:
- Successful isolation of hydroxy mercapto methylene (HO-C̈-SH) under cryogenic conditions.
- Identification of two stable carbene rotamers formed via ethylene and CO2 extrusion.
- Spectroscopic characterization of the CH2SO species, confirming it as a free mercapto carbene.
Conclusions:
- The study reports the first spectroscopic characterization of a free mercapto carbene.
- The findings introduce a previously uncharacterized CH2SO species.
- Computational results corroborate the experimental observations and proposed structure.
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