On the exchange reaction,, using hexafluoroacetone

Article abstract of DOI:10.1016/S0022-1139(00)82605-6

The reaction of λ³-phospha-diazetidin-thione, 1 with hexafluoroacetone (HFA) furnished not only the expected addition product, the λ⁵P-perfluoropinacolyl phosphorane, 2. In addition, HFA was observed to cause {A figure is presented} exchange in 2, and exclusive formation of a urea derivative, 3, was noted upon prolonged interaction of HFA with 2. Likewise, N,N,N′,N′,-tetramethylthiourea, 1, was found to be converted to N,N,N′,N′-tetrarmethylurea, 5, by HFA. The reactions were followed by ¹H-, ¹³C-, ¹⁹F- and ³¹P-n.m.r. spectroscopy.