4932-71-2Relevant academic research and scientific papers
(Z)- and (E)-1,2-Bis(phenylsulfonyl)ethylenes as Synthetic Equivalents to Acetylene as Dienophile
Lucchi, Ottorino De,Lucchini, Vittorio,Pasquato, Lucia,Modena, Giorgio
, p. 596 - 604 (2007/10/02)
A new method for introducing an ethylenic bridge via a cycloaddition reaction has been developed.It makes use of either (Z)- or (E)-1,2-bis(phenylsulfonyl)ethylene (5 or 6) as synthetic equivalents of acetylene.The high activation due to the two sulfonyl groups promotes cycloaddition even to very unreactive dienes.The removal of the two sulfonyl groups for the required formation of the carbon-carbon double bond is promoted by reduction with metal amalgams in high yields.These properties, associated with the stability of the reagents and the ease of performance of the reactions, make this method a very useful synthetic tool for the preparation of polycyclic dienes and a valid alternative to the commonly available reagents that largely depend upon oxidative methods.
GENERAL APPLICABILITY OF Z-1,2-DIPHENYLSULFONYLETHYLENE AS ACETYLENE SYNTHON IN CYCLOADDITION REACTIONS: A TWO STEP SYNTHESIS OF TETRACYCLO2,4.03,7>NON-8-ENE AND TRICYCLO2,5>NONA-3,7-DIENE
Lucchi, Ottorino De,Modena, Giorgio
, p. 229 - 232 (2007/10/02)
Z-1,2-diphenylsulfonylethylene is shown to be a dienophile of general use since not only it cycloadds to conjugated 1,3-dienes but also to homo-conjugated double bonds and strained ?-bonds as those of norbornadiene and quadricyclane.The adducts can be red
