82234-80-8Relevant academic research and scientific papers
A base-controlled regioselective synthesis of allyl and vinyl phenyl sulfones
Dana, Dibyendu,Davalos, Anibal R.,Subramaniam, Gopal,Afzal, Nisar,Hersh, William H.,Kumar, Sanjai
, p. 2717 - 2721 (2013/06/26)
A reaction of diethyl phenylsulfonylmethylphosphonate with 2-arylacetaldehydes in the presence of a catalytic excess of sodium hydride (1.1 equiv) yields allyl phenyl sulfones in excellent yield under mild reaction conditions. In contrast, when less than 1 equiv of sodium hydride (0.90 equiv) is used, the corresponding vinyl phenyl sulfones are obtained exclusively. The vinyl phenyl sulfones can be completely converted to allyl phenyl sulfones with only 0.2 equiv of NaH, suggesting that the second hydride involvement in the above transformation is catalytic. The regioselective control observed in these reactions offers a general method for synthesizing novel vinyl and allyl phenyl sulfones in one step from the same starting materials. The regioselectivity and stereoselectivity of this reaction, however, are not maintained when 2-alkylacetaldehydes are reacted with diethyl phenylsulfonylmethylphosphonate under identical reaction conditions. Our results indicate that an extended conjugation of the double bond in allylsulfones formed from the reaction of 2-arylacetaldehydes is required for the observed regio- and stereoselectivity.
Palladium-Catalyzed Substitutions of Allylic Nitro Compounds. Regiochemistry
Tamura, Rui,Kai, Yoshiki,Kakihana, Masato,Hayashi, Koji,Tsuji, Masanori,et al.
, p. 4375 - 4385 (2007/10/02)
Primary, secondary, and tertiary allylic nitro compounds underwent Pd(0)-catalyzed allylic substitution by stabilized carboanions, secondary amines, and benzenesulfinate ion (PhSO2-). α,β-disubstituted α-nitro olefins also behaved as allylic nitro compounds, via base-catalyzed vinyl -> allyl rearrangement, and underwent allylic substitution by secondary amines and PhSO2-.The regiochemistry of these substitutions was dependent on the structure of the allylic nitro compound amd on the steric bulk of the nucleophile.Generally, substitution occurred at the lesshindered or least substituted site.In some cases added or generated NaNO2 affected the regioselectivity of the allylic substitution of allylic nitro compounds and some allylic acetates by PhSO2-.Under these conditions, the more sterically hindered allylic sulfones were formed.
Carbon Dioxide-Promoted Telomerization of 1,2- and 1,3-Dienes with Benzenesulfinate Catalyzed by Palladium(0)
Inoue, Yoshio,Hashimoto, Harukichi
, p. 3705 - 3708 (2007/10/02)
The telomerization of 1,2- and 1,3-dienes with benzenesulfinate dihydrate catalyzed by palladium(0) has been promoted by the presence of carbon dioxide
PALLADIUM CATALYZED SYNTHESIS OF ALLYLIC SULFONES. UTILIZATION OF α-NITRO OLEFINS AS ALLYLIC NITRO COMPOUNDS
Tamura, Rui,Hayashi, Koji,Kakihana, Masato,Tsuji, Masanori,Oda, Daihei
, p. 229 - 232 (2007/10/02)
α-Nitro olefins reacted with sodium benzenesulfinate in the presence of tertiary amine and palladium(0) catalyst to afford allylic sulfones.The competition experiment showed that relative rate of the sulfonylation of an α-nitro olefin to that of the corre
Syntheses a l'aide de sulfones. XVIII. Utilisation des disulfones-1,1 pour la synthese stereoselective de composes olefiniques
Cuvigny, Therese,Penhoat, Catherine Herve Du,Julia, Marc
, p. 43 - 51 (2007/10/02)
2-Alkenyl-1,1-disulfones 4 are readily available in excellent yields by condensation of aldehydes with bisaryl or bisalkylsulfonylmethanes in the presence of piperidine acetate and molecular sieves at room temperature.A small amount of the 1-alkenyl isomer is also found when the aldehyde is α-substituted but it can be converted into the 2-alkenyl isomer by base catalysed equilibration.The 2-alkenyl-1,1-disulfones display only E geometry whereas E allylic monosulfones are difficult to isolate in a state of stereochemical purity (about 20percent of the Z isomer at equilibrium (8)).Alkylation is readily performed: treatment of 4 and 6 by sodium hydride in dimethylformamide and then by methyl iodide gives disulfones 5 E and 7 in 78-95percent yields.The alkylation of 4 (R=Et) by butyl iodide gives 70percent of 5 E(R=Et, R'=n-Bu) resulting from alkylation at the α position and 8percent of 3 (R=Et, R'=n-Bu) resulting from alkylation at the γ position.The α isomer is readily purified by crystallization.Reduction of disulfones 4 or 5 by aluminium amalgam leads quantitatively to allylic sulfones 2E or 8E.Olefins 9E are obtained upon total reduction of disulfones 4 or 5 by lithium in ethylamine at -78 deg C but in the case of disulfones 5 the olefins 9E are contaminated by isomers 10E and 10Z.
