Elimination and addition reactions. Part XXV. Addition–elimination reactions of phenoxyvinyl sulphones
作者:Marijke J. van der Sluijs、Charles J. M. Stirling
DOI:10.1039/p29740001268
日期:——
Reactions of cis- and trans-2-phenoxyvinyl p-tolyl sulphones with alcoholic alkoxides have been studied. Product analyses and kinetic studies show that in each case a two-stage addition–elimination pathway is followed. The elimination step is assigned the (E1cB)R mechanism on the basis of measurements carried out in deuteriated solvents. The rate constants and activation parameters for both addition
Alkylation of 2-oxy-substituted 1-sulfonylallyl and 1-sulfonylvinyl anions. New routes to functionalized carbocycles and dihydrofurans
作者:Albert Padwa、William H. Bullock、Andrew D. Dyszlewski、S. W. McCombie、B. B. Shankar、A. K. Ganguly
DOI:10.1021/jo00011a021
日期:1991.5
Alkylation of the anion derived from 2-phenoxy-3-(phenylsulfonyl)-1-propene proceeds alpha to the phenylsulfonyl group and affords cyclic products from 1,omega-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.
Ohta, Yakugaku Zasshi/Journal of the Pharmaceutical Society of Japan, 1948, vol. 68, p. 216
作者:Ohta
DOI:——
日期:——
PADWA, ALBERT;BULLOCK, WILLIAM H.;DYSZLEWSKI, ANDREW D.;MCCOMBIE, S. W.;S+, J. ORG. CHEM., 56,(1991) N1, C. 3556-3564
作者:PADWA, ALBERT、BULLOCK, WILLIAM H.、DYSZLEWSKI, ANDREW D.、MCCOMBIE, S. W.、S+