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Sulfonyl Carbenes

In contrast to this behavior stabilized sulfonyl ylides 125 lose PhjP under flash vacuum pyrolysis conditions to give sulfonyl carbenes 127 which evolve to the formation of various products among which the alkenes 129, observed in all the cases (Scheme 35) [129]. [Pg.68]

V. ADDITION OF SULFONYL CARBENES AND SULFONYL NITRENES A. Sulfonyl Carbenes... [Pg.809]

In principle, the vinylcarbene-to-cyclopropene isomerization is reversible. While this has not been reported for 167 (where ring-opening could produce not only alkenyl(sulfonyl)carbene 166, but also the isomeric l-alkenyl(silyl)carbene), it was found that 1-trimethylsilylcyclopropenone acetal 168 (equation 49) by thermal ring-opening yields the (trimethylsilyl)vinylcarbene 169 besides traces of the isomeric vinylcarbene 170. Both carbenes are obviously nucleophilic since they are able to cyclopropanate the... [Pg.745]

Decomposition (usually photolytic) of the corresponding diazo compounds generates sulfonyl-or organo(sulfonyl)carbenes which in the presence of alkenes form cyclopropane derivatives. ... [Pg.781]

Generation of cyclic organothio(sulfonyl)carbenes which undergo addition to nucleophilic al-kenes to give spiro-products 2, require the use of butyllithium as a base. ... [Pg.782]

Bis(sulfonyl)carbene (carbenoid) is generated photolytically, thermally or catalytically from bis(sulfonyl)diazomethane or from the corresponding phenyliodonium ylide (Houben-Weyl, Vol. E19b, ppl735, 1739-1743). In the latter case only, the carbene reacts with an alkene to form l,l-bis(sulfonyl)cyclopropanes (Houben-Weyl, Vol. E19b, pl743). [Pg.782]

In our search for carbenes with even higher electrophilicity we found that B3LYP calculations predict bis(sulfonyl)carbenes 3 to have EAs above 4 eV. These highly electrophilic carbenes have been studied in detail in our laboratory and are described in this chapter. [Pg.8]

Zweifach sulfonierte Schwefelylide (103) entstehen bei Photolyse und Thermolyse des Bis-phenylsulfonyl-diazomethans in Gegenwart von Thioathem oder Sulfoxyden, vermutlich durch Abfangen des Bis-(phenyl-sulfonyl)-carbens (22). [Pg.35]

Schank, K., Organothio-Sulfinyl-and Sulfonyl-carbene, Houben Weyl, E 19b/Teilband 2, Thiema Verlag, Stuttgart, 1989. [Pg.1870]

See other pages where Sulfonyl Carbenes is mentioned: [Pg.759]    [Pg.759]    [Pg.809]    [Pg.809]    [Pg.759]    [Pg.759]    [Pg.260]    [Pg.748]    [Pg.781]    [Pg.782]    [Pg.782]    [Pg.781]    [Pg.781]    [Pg.782]    [Pg.782]    [Pg.545]    [Pg.22]    [Pg.22]   


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Sulfonyl Triazoles as Stable Carbene Precursors

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