140396-96-9Relevant academic research and scientific papers
Studies on an Oxidative 1,4-Addition to s-trans-1,3-Dienes, a Key Reaction in a Strigol Total Synthesis
Galkina, Anna,Buff, Angelika,Schulz, Emmanuelle,Hennig, Lothar,Findeisen, Matthias,Reinhard, Gerd,Oehme, Ramona,Welzel, Peter
, p. 4640 - 4653 (2007/10/03)
Oxidation of 4,6-heptadienoic acid systems with hydrogen peroxide in the presence of a catalytic amount of diphenyl diselenide leads to 5-(3-hydroxypropenyl)dihydrofuran-2-one systems with defined relative configuration at the 4 and 7 positions (carboxylic acid numbering). A system having a six-membered ring as part of the s-trans-diene system was an intermediate in a strigol total synthesis; a second system lacking the six-membered ring is the subject of the present publication. We accomplished a stereoselective synthesis of the diene system by (i) trapping a π-allyl palladium complex with lithium diphenylphosphinite to give an allylic diphenylphosphane oxide and (ii) a subsequent Horner-Wittig reaction. The species that brings about the oxidative 1,4-addition is benzeneperoxyseleninic acid. We also report observations that shed some light on the mechanism. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
Phosphazene base P2-Et mediated isomerization of vinyl sulfones to allyl sulfones
Jin, Zhendong,Kim, Seong Heon,Fuchs
, p. 5247 - 5248 (2007/10/03)
Treatment of vinyl sulfones with 0.1-0.2 eq of Phosphazene base, P2-Et in THF at 25°C affords the corresponding allyl sulfones in high yield. P2-Et has shown clear superiority to both DBU and KO-t-Bu in these reactions.
The Strain Limit in Intramolecular Nucleophilic Substitution
Jeffery, Stephen M.,Stirling, Charles J. M.
, p. 1617 - 1624 (2007/10/02)
Kinetics and products of reactions of sulfonyl-stabilised carbanions bearing ω-leaving groups have been examined.The intention was to explore the upper limit of strain that can be tolerated for intramolecular nucleophilic substitution in these systems and
BIS-ALKYLATION OF DIMETALLATED PHENYLSULFONYLMETHYL TRIFLONE. A n+1 ANNULATION STRATEGY FOR SYNTHESIS OF CYCLIC VINYL SULFONES
Magar, S. S.,Fuchs, P. L.
, p. 745 - 748 (2007/10/02)
Bis-metallation of phenylsulfonylmethyl triflone 4b produces a geminal dianion which can be dialkylated to afford α-phenylsulfonyl triflones.Treatment of these compounds with DBU affords vinyl sulfones which can be isomerized to allyl sulfones.
Strain-induced Mechanism Change: the Limit of Strain Tolerance in Intramolecular Nucleophilic Substitution?
Jeffery, Stephen M.,Niedoba, Stefan,Stirling, Charles J. M.
, p. 650 - 652 (2007/10/02)
The limit of strain energy differential for intramolecular nucleophilic substitution via a sulfonyl-stabilised carbanion to give cyclopropane analogues in hydroxylic solvents is around 160 kJ mol-1; above this level, concerted, albeit unactivat
