A Convenient Synthesis of Terminal Perfluoroacylacetylenes and Perfluoroalkynals

Synthesis, structure and pyrolysis of stabilised phosphonium ylides containing saturated oxygen heterocycles

“…In previous such cases there has been little selectivity with almost equal proportions of the two possible products being formed. 34,35 This also proved to be the case here, with compound 9 undergoing complete extrusion of Ph 3 PO at 500°C to afford a mixture of 37 (26%) and 39 (58%), while the benzoyl compound 10 gave a mixture of 38 (29%) and 40 (30%) under the same conditions (Scheme 9). All these alkynyl ketone products are previously unknown.…”

Fluorinated Ylides and Related Compounds

“…Usually the reactant ylide is easily prepared and the product ylide is more complex. For the preparation of fluorine-containing stabilized phosphonium ylides, the starting ylide could be either fluorinated or nonfluorinated and the electrophiles usually were fluorinated compounds such as fluorinated esters, − acid halides, ,− anhydrides, − aromatics, olefins, epoxides, or ketophosphonium salts. , This strategy is illustrated in eq 97, and the results are summarized in Table . In these reactions, the reactant ylide 12 underwent an addition−elimination process with an appropriate electrophile to form a phosphonium salt intermediate 13 which was then deprotonated by a second mole of the ylide to give a new ylide 14 .…”

Flash vacuum pyrolysis of stabilised phosphorus ylides. Part 5. Selective extrusion of PH3PO from β,γ,β′-trioxo ylides to give diacylalkynes

“…Prepared as colourless crystals (56%), 72.4;H,5. 7.8-7.4 ( 1 5 H, m), 3.83 (2 H, q, J 7), 2.32 (3 H, s) and 0.78 (3 H, t, J 7); 6, see Table 2; BP + 15.2; m/z 418 (M', 0.2%),375 (M+ *-COMe, loo), 347 ( 3 , 303 (28), 301 (36), 277 (67), 262 (70), 201 (37), 183 (86) and 165 (40).…”