244266-71-5Relevant academic research and scientific papers
Intramolecular cationic cyclization of β-hydroxyalkylphosphine oxides—a route towards the benzophosphorinane core
W?odarczyk, Katarzyna,Stankevi?, Marek
, p. 5074 - 5090 (2016/07/25)
Intramolecular cationic cyclization of β-hydroxyalkylphosphine oxides in the presence of an acid lead to the formation of fused bicyclic compounds with an incorporated phosphorus atom. Depending on the structure of the starting compound the formation of e
Palladium-catalyzed cascade reaction of α,β-unsaturated sulfones with aryl iodides
Mauleon, Pablo,Nunez, Angel A.,Alonso, Ines,Carretero, Juan C.
, p. 1511 - 1520 (2007/10/03)
Unlike traditionally used acyclic 1,2-disubstituted alkenes, the reaction of α,β-unsaturated phenyl sulfones with aryl iodides under Heck reaction conditions (Pd(OAc)2 as catalyst, Ag2-CO3 as base in DMF at 120°C) takes place mainly by a cascade process, involving one unit of the alkene and three units of the aryl iodide, to afford a substituted 9-phenylsulfonyl-9,10-dihydrophenanthrene, The dominant formation of this 3:1 coupling product, instead of the Heck trisubstituted olefin, shows that aromatic C-H activation processes can compete with the usually fast syn β-hydrogen elimination step in the Heck arylation of an acyclic olefin. The structural scope of this palladium-catalyzed cascade arylation of α,β-unsaturated sulfones has proved to be wide with regard to substitution at the β-position (alkyl, aryl, or alkenyl substitution), substitution at the sulfone unit (alkyl or phenyl sulfones), and configuration at the C=C bond (trans or cis). Moreover, although less favored than in the case of the arylation of α,β-unsaturated sulfones, similarly substituted 9,10-dihydrophenanthrenes have also been obtained in the case of α,β-unsaturated phosphine oxides and α,β-unsaturated phosphonate esters. A Pd0-pdII-pdIV mechanistic pathway involving the successive formation of highly electrophilic σ-alkylpalladium intermediates and palladacycles is proposed for this multi-component arylation.
Diastereoselective nucleophilic additions to vinyl phosphine oxides
Barteis, Bjoern,Ciayden, Jonathan,Martin, Concepcion Gonzalez,Neison, Adam,Russell, Matthew G.,Warren, Stuart
, p. 1807 - 1822 (2007/10/03)
Some hydrogen, carbon, silicon, sulfur, nitrogen and oxygen nucleophiles react diastereoselectively with γ-oxygenated chiral vinyl phosphine oxides to give β-substituted phosphine oxides. Lithium N-benzyl-α-methylbenzylamide adds to prochiral vinyl phosphine oxides in the presence of trimethylsilyl chloride to provide, after protodesilylation, β-amino phosphine oxides as single diastereoisomers.
Stereochemistry of direct olefin formation from carbonyl compounds and lithiated heterocyclic sulfones
Baudin, J. B.,Hareau, G.,Julia, S. A.,Lorne, R.,Ruel, O.
, p. 856 - 878 (2007/10/02)
The conditions for the title reaction were studied for the 2-benzothiazole and 2-pyridine series and for some examples in the 2-pyrimidine series.The olefin preparations were generally observed to be more efficient for 2-BT-sulfone systems.From the data of the hundred cases studied, it can be concluded that (E)-olefins are obtained: (i) from saturated BT-sulfones and aromatic aldehydes; and (ii) from benzylic BT-sulfones and branched saturated aldehydes (isobutyraldehyde, pivalaldehyde) or α,β-ethylenic or aromatic aldehydes. (Z)-olefins arise: (i) fom propargylic BT-sulfones and saturated or aromatic aldehydes; and (ii) from allylic or benzylic Pyr-sulfones and saturated aldehydes.Possible mechanisms for this new olefination procedure were examined. - heteroaromatic sulfones, organolithium derivatives, intramolecular ipso reactions, stereochemistry, elimination, olefination.
