100867-08-1Relevant articles and documents
Polymer-supported triphenylphosphine ditriflate: A novel dehydrating reagent
Elson, Kathryn E.,Jenkins, Ian D.,Loughlin, Wendy A.
, p. 2491 - 2493 (2004)
A new type of polymeric dehydrating reagent, readily prepared by the treatment of polymer-supported triphenylphosphine oxide with triflic anhydride, was found to be effective in a variety of dehydration reactions such as ester and amide formation; the polymer-supported triphenylphosphine oxide was easily recovered and reused several times without the loss of activity.
Novel polymer-supported coupling/dehydrating reagents for use in organic synthesis
Fairfull-Smith, Kathryn E.,Jenkins, Ian D.,Longhlin, Wendy A.
, p. 1979 - 1986 (2007/10/03)
Two novel dehydrating reagents 3 and 4, based on a phosphonium anhydride and an oxyphosphonium triflate respectively, were prepared by reaction of the corresponding polymer-supported phosphine oxides with triflic anhydride. Reagent 3, based on the novel phosphorus heterocycle 1,1,3,3-tetraphenyl-2-oxa-1,3- diphospholanium bis(trifluoromethanesulfonate), was found to be a useful reagent for ester and amide formation. A wide range ofcoupling/dehydration-type reactions, such as ester, amide, anhydride, peptide, ether and nitrile formation, were performed in high yield using the more readily prepared polymer-supported triphenylphosphine ditrinate 4, which was easily recovered and re-used several times without loss of efficiency. With primary alcohols, both reagents 3 and 4 provide an alternative to the Mitsunobu reaction, where the use of azodicarboxylates and chromatography to remove the phosphine oxide by-product can be avoided. The use of 4-dimethylaminopyridine allowed the esterification of secondary alcohols with 4 to proceed in high yield but with retention of configuration.
The α-Effect in Benzyl Transfers from Benzylphenylmethyl Sulfonium Salts to N-Methylbenzohydroxamate Anions
Fountain,Tad-y, Darlene B.,Paul, Timothy W.,Golynskiy, Mikhail V.
, p. 6547 - 6553 (2007/10/03)
The investigation of the occurrence of the α-effect in group transfers from phenyldialkyl sulfonium ions where one alkyl group is benzyl allows an assay of the effect of changing the nature of the C atom being transferred. The size of the α-effect responds to increasing electron demand, as methyl transfers do. Quantitative relationships between the size of the α-effect are established from both the nucleophilic side and the leaving group side of the SN2 transition state.