862891-86-9Relevant academic research and scientific papers
Conformation and stereodynamics of 2,2′-disubstituted N,N′-diaryl ureas
Clayden, Jonathan,Lemiegre, Loic,Pickworth, Mark,Jones, Lyn
, p. 2908 - 2913 (2008)
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.
Ring-selective functionalization of N,N′-diarylureas by regioselective N-alkylation and directed ortho metalation
Clayden, Jonathan,Turner, Hazel,Pickworth, Mark,Adler, Thomas
, p. 3147 - 3150 (2007/10/03)
(Chemical Equation Presented) Unsymmetrical N,N′-diarylureas may be alkylated regioselectively at the more sterically congested nitrogen atom. The resulting mono-N-alkylated ureas undergo directed metalation (ortholithiation) with sec-BuLi to yield, on el
