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Vinyl trifluoromethanesulfonates

Vinyl trifluoromethanesulfonates (triflates) are a new class of compounds, unknown before 1969, that have been used most extensively in solvolytic studies to generate vinyl cations.2,3,812 Three methods have been used to prepare these sulfonic esters. The first, involving the preparation and decomposition of acyltriazines,4 requires several steps to prepare the acyltriazines and is limited to the preparation of fully substituted vinyl triflates. The second method involves the electrophilic addition of trifluoromethanesulfonic acid to acetylenes5,8,15 and, consequently, is not applicable to the preparation of trisubstituted vinyl triflates and certain cyclic vinyl triflates. However, this second procedure is relatively simple and often gives purer products in higher yield than the subsequently discussed reaction with ketones. Table I lists vinyl triflates that have been prepared by this procedure. ... [Pg.41]

PALLADIUM-CATALYZED REDUCTION OF VINYL TRIFLUOROMETHANESULFONATES TO ALKENES CH0LESTA-3.5-DIENE... [Pg.70]

Vinyl trifluoromethanesulfonates have provided a solution to this... [Pg.191]

Vinyl trifluoromethanesulfonates (triflates). Vinyl triflates are available by two procedures. In one, an acetylene is treated with the acid at low temperatures ... [Pg.270]

Vinylmagnesium bromide, 251 Vinylmagnesium chloride, 221, 572 Vinyl trifluoromethanesulfonates, 533 3-Vinyl-3,5,5-trimethylcyclohexanone, 221 Vinyl triphenylphosphonium bromide, 572 Vitamin A acetate, 16 Vitamin A alcohol, 372 Vitamin B, 2, 82... [Pg.334]

Substitution reactions of sp halides have been achieved with the aid of a palladium catalyst (Scheme 23). 14,19 variety of aryl bromides and iodides serve as electrophiles. Reactions with vinyl halides are stereospecific. Vinyl trifluoromethanesulfonates (triflates) also react rapidly with homoenolates. [Pg.449]

Vinyl trifluoromethanesulfonates16 have provided a solution to this problem. Vinyl trifluoromethanesulfonates can be formed by the action of trifluoromethanesulfonic anhydride with a ketone.4,16 Enolates may be trapped using N-phenyltrifluoromethanesulfonimide to form selectively either the... [Pg.125]

Stang, P. 0. Hanack, M. Subramaniam, L. R. Synthesis, 1982, 85-126. For a review of the use of vinyl trifluoromethanesulfonates as electrophiles in carbon-carbon bond forming reactions, see Scott, VI. [Pg.127]

See other pages where Vinyl trifluoromethanesulfonates is mentioned: [Pg.191]    [Pg.191]    [Pg.192]    [Pg.22]    [Pg.95]    [Pg.39]    [Pg.22]    [Pg.125]    [Pg.127]    [Pg.125]    [Pg.125]    [Pg.127]   
See also in sourсe #XX -- [ Pg.533 ]



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