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Updated: Oct 11, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Crystal structure of 2-oxo-1,2-di-phenyl-ethyl diiso-propyl-carbamate
Viktor Martens1, Helmar Görls2, Wolfgang Imhof1
1Institute of Integrated Natural Sciences, University Koblenz - Landau, Universitätsstr. 1, 56070 Koblenz, Germany.
Abstract:
The title compound, C21H25NO3, crystallized as a racemic twin in the Sohnke space group P21. In the mol-ecular structure of the title compound, both enanti-omers show a highly similar conformation with the urethane function and the benzoyl group showing an almost perpendicular arrangement [the dihedral angle is 72.46 (8)° in the S-enanti-omer and 76.21 (8)° in the R-enanti-omer]. In the crystal structure, mol-ecules of both enanti-omers show infinite helical arrangements parallel to the b axis formed by weak C-H⋯O hydrogen bonds between the phenyl ring of the benzoyl group and the carbamate carbonyl group. In case of the R-enanti-omer, this helix is additionally stabilized by a bifurcated hydrogen bond between the carbonyl function of the benzoyl group towards both phenyl groups of the mol-ecule.
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