Cycloaddition of 3,4-Dimethoxyfuran with 1,4-Benzoquinones under High Pressure
作者:Janusz Jurczak、Tomasz Ko??gluk、Marek Tkacz、Conrad Hans Eugster
DOI:10.1002/hlca.19830660122
日期:1983.2.2
High-pressure cycloaddition of 3,4-dimethoxyfuran with 1,4-benzoquinone, toluquinone and 2,3-dimethoxy-1,4-benzoquinone show, at 7 kbar and room temperature, prevailing formation of endo-isomers. Raising pressure (or temperature) results in a surprising increase of the exo-isomer. By catalytic hydrogenation of a mixture 3a/4a, followed by chromatography, the pure diastereomers 5 and 6 were obtained
Stability of cycloadducts obtained by high-pressure Diels-Alder reaction between 3,4-dimethoxyfuran and 1,4-benzoquinones: kinetic studies of retro-Diels-Alder reaction
作者:Janusz Jurczak、Andrzej L. Kawczynski、Tomasz Kozluk
DOI:10.1021/jo00207a035
日期:1985.4
HOFMANN A. A.; WYRSCH-WALRAF I.; ITEN P. X.; EUGSTER C. H., HELV. CHIM. ACTA, 1979, 62, NO 7, 2211-2217
作者:HOFMANN A. A.、 WYRSCH-WALRAF I.、 ITEN P. X.、 EUGSTER C. H.
DOI:——
日期:——
JURCZAK, J.;KOZLUK, T.;TKACZ, M.;EUGSTER, C. H., HELV. CHIM. ACTA, 1983, 66, N 1, 218-221
作者:JURCZAK, J.、KOZLUK, T.、TKACZ, M.、EUGSTER, C. H.
DOI:——
日期:——
SYNTHETIC STUDIES ON THE DIELS–ALDER ADDUCT FROM 3,4-DIMETHOXYFURAN AND BENZOQUINONE
作者:Mauricio Gomes Constantino、Adilson Beatriz、Gil Valdo José da Silva、Julio Zukerman-Schpector
DOI:10.1081/scc-100106044
日期:2001.1
In this paper we describe the peculiar properties of a polycyclic compound (2), derived from a Diels–Alder adduct, which undergoes spontaneous cyclization to 3 when kept in chloroform solution. Stable intermediates needed for our studies on the synthesis of heliangolides were obtained only after reduction of the double bonds of 2.