Solvent-dependent crystallization of 1-hydro-6-carbaphosphatrane and its tautomer.
1-Hydro-6-carbaphosphatrane 2 was obtained as a mixture with its tautomer, 3. Tautomers 2 and 3 were isolated by the recrystallization from different solvents, respectively, and each structure was determined by X-ray crystallographic analysis. Variable-temperature NMR experiments revealed that pentacoordinate 2 and tricoordinate 3 are under the equilibrium, showing that 3 is more stable. The theoretical calculations found a weaker transannular PC bond in 2 than in 1-hydro-5-carbaphosphatrane, 1, which can be considered to be the reason 1-hydro-6-carba-phosphatrane 2 is less stable than its tautomer 3.
Nakafuji
Shin-ya
SY
Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Kobayashi
Junji
J
Kawashima
Takayuki
T
Schmidt
Michael W
MW