R. Buchel et al., ,3,3,4,4,5,5,5-NONAFLUOROPENTYL)IMIDAZOLIDIN-4-ONE AT 100-K, Acta crystallographica. Section C, Crystal structure communications, 50, 1994, pp. 1803-1805
The imidazolidinone ring of the title compound, C20H21F9N2O2(2), adopt
s an envelope conformation with the tert-butyl and nonafluoropentyl gr
oups in a trans arrangement with respect to the ring. The angles at ea
ch N atom total nearly 360 degrees, indicating a very small degree of
pyramidalization at the two amides. The torsional angles C(1)-N(2)-C(2
)-O(1), C(3)-N(1)-C(4)-O(2) and C(1)-N(1)-C(4)-O(2) deviate from 180 o
r 0 degrees by 7.1, 25.5 and 10.4 degrees, respectively. This is consi
stent with considerable conjugative stabilization in both amide groups
.