The use of squaric acid as a scaffold for cofacial phenyl rings.
[structure: see text] To examine the possibility of using squaric acid as a scaffold for organizing phenyl rings in a cofacial orientation, we undertook an investigation of the conformational preferences of secondary and tertiary N-phenylsquaramides. In secondary squaramides, the extended ZZ conformation is preferred, while in the N-methyl derivative, the folded EE conformation with cofacial phenyl rings is preferred. This conformational switch is likely driven by a combination of steric and electronic factors.
Muthyala
Rajeev S
RS
Department of Chemistry and Biochemistry, Queens College and the Graduate Center of the City University of New York, Flushing, New York 11367-1597, USA. rajeev_muthyala@qc.edu
Subramaniam
Gopal
G
Todaro
Louis
L