81665-71-6Relevant academic research and scientific papers
Synthesis of ortho-substituted arylacetic esters and related compounds by means of Sommelet-Hauser rearrangement of sulfur ylides
Ishibashi,Tabata,Kobayashi,Takamuro,Ikeda
, p. 2878 - 2882 (2007/10/02)
The rearrangement of a series of dimethylsulfonium α-substituted benzylides, e.g., 8, in ethanol has been examined. The ylides 8a,b generated in situ by treatment of the sulfonium salts 7a,b with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in ethanol at room temperature, afforded the o-(methylthiomethyl)phenylacetic esters 10a,b as a result of the Sommelet-Hauser rearrangement of the tautomeric ylides 9a,b. By contrast, the ylide 14 possessing afuran ring was stable at room temperature, but, on heating in ethanol, gave the rearranged product 15. The ylide 22 stabilized by an acetyl group provided three rearranged products, 23, 24, and 25, in boiling ethanol. Treatment of the sulfonium salts 30a,b with DBU at room temperature afforded the corresponding rearranged products 31a,b. The sulfonium salt 34a prepared from 33a, on treatment with sodium ethoxide, gave the rearranged product 36a, which was then S-methylated and treated with DBU to give the 1,2,3-trisubstituted benzene 37a. This method was applied to the synthesis of the fenoprofen analog 39 from 39 from 33b,c.
Synthesis of Ethyl Arylacetates by Means of Friedel-Crafts Reaction of Aromatic Compounds with Ethyl α-Chloro-α-(methylthio)acetate
Tamura, Yasumitsu,Choi, Hong Dae,Shindo, Hirohisa,Ishibashi, Hiroyuki
, p. 915 - 921 (2007/10/02)
Friedel-Crafts reaction of aromatic compounds with ethyl α-chloro-α-(methylthio)acetate (1) gave ethyl α-(methylthio)arylacetates (2), which were readily converted into ethyl arylacetates (3) by reductive desulfurization with Raney nickel or zinc dust-acetic acid.The reactions were applied to the syntheses of ibufenac (5) and alclofenac (6), which are anti-inflammatory agents.
ELECTROPHILIC AROMATIC SUBSTITUTION BY PUMMERER REACTION OF α-SULFINYLACETATE
Tamura, Y.,Choi, H.-D.,Shindo, H.,Uenishi, J.,Ishibashi, H.
, p. 81 - 84 (2007/10/02)
Treatment of a mixture of aromatic compound and ethyl α-(methylsulfinyl)acetate (5) with p-toluenesulfonic acid under continuous removal of separated water brought about an intermolecular aromatic substitution to give ethyl α-(methylthio)arylacetate (6).S
