93958-25-9Relevant academic research and scientific papers
CYCLIC ENEDIOL PHOSPHORANES OBTAINED FROM THE REACTION OF TRIMETHYL PHOSPHITE WITH BIACETYL AND HEXAFLUOROBIACETYL GIVE STRIKINGLY DIFFERENT ACYLATION PRODUCTS
Ramirez, Fausto,Marecek, James, F.
, p. 2837 - 2842 (1984)
Cyclic enediol phosphoranes (2,2,2-trimethoxy-2,2-dihydro-1,3,2-dioxaphospholenes), prepared from α-diketones, RCOCOR, and trimethyl phosphite (TMP), give strikingly different acylation products depending on the electronic properties of the groups, R, that occupy the 4,5-positions in the dioxaphospholene ring with pentacovalent phosphorus.Reaction of acetyl chloride or bromide with hexafluorobiacetyl-TMP phosphorane gives exclusively the product of endocyclic O-acylation, dimethyl-(2-acetoxy-cis-1,2-bistrifluoromethylvinyl) phosphate.Acylation of the biacetyl-TMP phosphorane gives mixtures of the product of exocyclic O-acylation (a cyclic enediol phosphate) and the product of C-acylation (an α-hydroxy-β-diketone phosphate), the proportions depending on the structure of the acyl halide and the solvent.The parent 1,2,3-dioxaphospholene, i.e., the glioxal-TMP phosphorane where R=H, gives exclusively the product of endocyclic O-acylation with both acyl halides in all solvents.
