131616-55-2Relevant academic research and scientific papers
Alkylation of 2-Oxy-Substituted 1-Sulfonylallyl and 1-Sulfonylvinyl Anions. New Routes to Functionalized Carbocycles and Dihydrofurans
Padwa, Albert,Bullock, William H.,Dyszlewski, Andrew D.,McCombie, S. W.,Shankar, B. B.,Ganguly, A. K.
, p. 3556 - 3564 (2007/10/02)
Alkylation of the anion derived from 2-phenoxy-3-(phenylsulfonyl)-1-propene proceeds α to the phenylsulfonyl group and affords cyclic products from 1,ω-dihalides.Reaction of the monoalkylated products, in which a suitably positioned olefinic or acetylenic unit is present, with sodium benzenesulfinate-acetic acid gives functionalized acetylcyclopentenes and cyclohexenes via C-C bond formation from the allyl cation-sulfinate ion pair.In the vinyl sulfone series, deprotonation of (E)- or (Z)-2-alkoxyvinyl phenyl sulfones rapidly affords the more stable (E)-lithio derivative, an acetaldehyde anion equivalent which reacts normally with aldehydes, ketones, alkyl halides, and epoxides.The latter process may be effected in an intramolecular fashion.Thus, (E)-(2-phenylsulfonyl)vinyl ethers of 2,3-epoxy alcohols cyclize on treatment with amide bases to afford dihydrofurans whose stereochemistry is fully defined by that of the starting epoxy alcohol.
Approaches to 2,6-Diaryl-3,7-DioxabicycloOctane Lignans via Asymmetric Synthesis of Dihydro- and Tetrahydro-furan Derivatives
Pelter, Andrew,Ward, Robert S.,Little, Gillian M.
, p. 2775 - 2790 (2007/10/02)
Cyclisation of chiral non-racemic phenylsulphonylvinyl epoxy ethers, produced using the Sharpless epoxidation reaction, has been used to prepare a series of enantiomerically enriched 2-aryl-4-(α-hydroxybenzyl)-4,5-dihydrofuran derivatives.Reduction of these compounds using triethylsilane and BF3-diethyl ether gave the corresponding tetrahydrofuran derivatives stereoselectively.Attempts to convert either the dihydro- or tetrahydro-furan derivatives into lignans belonging to the 2,6-diaryl-3,7-dioxabicyclooctane series so far proved unsuccessful.
CYCLOFUNCTIONALISATION OF EPOXYALCOHOL DERIVATIVES. 1. DELIVERY OF FUNCTIONALISED CARBON FOR STEREOSPECIFIC SYNTHESIS OF DIHYDROFURANS AND DIHYDROXYACIDS
McCombie, Stuart W.,Shankar, Bandarpalle B.,Ganguly, Ashit K.
, p. 6301 - 6304 (2007/10/02)
E-2-(Phenylsulfonyl)vinyl ethers of 2,3-epoxyalcohols are stereospecifically rearranged to 3-(phenylsulfonyl)-4-(1-hydroxyalkyl)-4,5-dihydrofurans on treatment with LDA.Oxidation of these compounds or the derived des-sulfonyl compounds provides esters or lactones which correspond to regiospecific delivery of -CO2H or -CH2CO2H to C-2, with inversion.
