959558-33-9Relevant academic research and scientific papers
Conformation and stereodynamics of 2,2′-disubstituted N,N′-diaryl ureas
Clayden, Jonathan,Lemiegre, Loic,Pickworth, Mark,Jones, Lyn
supporting information; experimental part, p. 2908 - 2913 (2009/02/02)
Except in the most hindered of cases, N,N′-diaryl N,N′-dimethyl ureas adopt a conformation with the two aryl rings disposed cis to one another. Variable temperature NMR studies reveal the rate at which the Ar-N bonds rotate as well as the conformational preference of ortho disubstituted ureas in which more than one cis orientation is possible. In general, a conformation in which the aryl rings lie close in space but with their most bulky 2-substituents aligned anti is preferred, but with particularly bulky 2-substituents, conformations in which one of the aryl rings points away from the other may also be populated. The Royal Society of Chemistry.
