73116-90-2Relevant articles and documents
Reaction of Tetramethyl-1,2-dioxetane with Triphenylphosphine: Activation Parameters for the Formation of 2,2-Dihydro-4,4,5,5-tetramethyl-2,2,2-triphenyl-1,3,2-dioxaphospholane
Baumstark, Alfons L.,Barrett, Morgan,Kral, Kathleen M.
, p. 201 - 203 (2007/10/02)
The reaction of tetramethyl-1,2-dioxetane (1) and triphenylphosphine (2) in benzene-d6 produced 2,2-dihydro-4,4,5,5-tetramethyl-2,2,2-triphenyl-1,3,2-dioxaphospholane (3) in about 90percent yield over the temperature range 6-60 deg C.Pinacolone and triphenylphosphine oxide (4) were the major side products .Thermal decomposition of 3 produced only 4 and 5.Kinetic studies were carried out by the chemiluminescence method.The rate of phosphorane was found to be first order with respect to each reagent.The activation parameters for the reaction of 1 and 2 were: Ea = 9.8+/-0.6 kcal/mole; ΔS = -28 eu; k30 deg C = 1.8 m-1sec-1 (range = 10-60 deg C).Preliminary results for the reaction of 1 and tris(p-chlorophenyl)phosphine were Ea about 11 kcal/mol, ΔS = -24 eu, k30 deg C = 1.3 M-1sec-1 while those for the reaction of 1 and tris(p-anisyl)phosphine were: Ea about 8.6 kcal/mol, ΔS = -29 eu k30 deg C = 4.9 M-1sec-1.
