149731-55-5Relevant academic research and scientific papers
Synthesis of 4-nitrophenyl sulfones and application in the modified Julia olefination
Mirk, Daniela,Grassot, Jean-Marie,Zhu, Jieping
, p. 1255 - 1259 (2007/10/03)
4-Nitrophenyl (NP) sulfones have been successfully employed in the modified Julia olefination reaction with carbonyl compounds. The olefination reaction proceeds through a sequence of aldol addition, Smiles rearrangement, and elimination. The sulfones are easily prepared in high yields in a two-step sequence starting from inexpensive commercially available para- fluoronitrobenzenes via nucleophilic aromatic substitution by a mercaptane and subsequent oxidation under standard conditions. The modified Julia reaction between NP sulfones and a wide variety of aromatic aldehydes affords the corresponding styrenes, stilbenes and cinnamate derivatives in yields up to 97% and good stereoselectivities. A mechanistic rationale is advanced to explain the observed results. Georg Thieme Verlag Stuttgart.
Platinum oxide catalyzed hydrosilylation of unsymmetrical internal aryl alkynes under ortho-substituent regiocontrol
Hamze, Abdallah,Provot, Olivier,Alami, Mouad,Brion, Jean-Daniel
, p. 5625 - 5628 (2007/10/03)
(Chemical Equation Presented) PtO2- and H2PtCl 6-catalyzed hydrosilylation of internal aryl alkynes having a para or an ortho substituent with triethylsilane are discussed and compared. The regioselectivity of the H-Si bond addition was found to be controlled by the ortho substituent rather than the nature of the platinum catalyst. Arylalkynes with an ortho substituent, regardless of its electronic nature, directed the silyl substituent mainly to the α-position. PtO2 proved to be a versatile and powerful catalyst compared to H2PtCl6 since it prevents the alkyne reduction.
