Novel Classes of Alkynyliodonium Salts and Their Applications: The Synthesis of Substituted 1,3-Diynyliodonium Triflates, R - C≡C - C≡C - I???? - Ph^-OTf, and Their Reaction with Triphenylphosphine

Organic Polyvalent Iodine Compounds

“…) CN, R ) CF 3 ), which is a highly efficient iodonium transfer reagent in the syntheses of various alkynyl and alkenyl(phenyl)iodonium salts. [60][61][62][63][64][65][66][67][68] Acids or acid anhydrides also react with PhIO with the formation of PhIX 2 or similar derivatives. Addition of triflic anhydride to 2 equiv of PhIO at 0 °C gives a bright yellow precipitate of µ-oxobis[(trifluoromethanesulfonyloxy)iodobenzene] 9 (Zefirov's reagent) (eq 3), a useful reagent for the preparation of iodonium salts.…”

“…Likewise, this procedure is applicable to the synthesis 63 of both conjugated 302 (eq 154) and unconjugated 303 (eq 155) bisiodonium salts. Diynyl(phenyl)iodonium triflates 304 (eq 156) have also been prepared 68 by the use of 287. In contrast, reaction of either 9 or activated PhIO with silaacetylenes afford [377][378][379][380] only β-alkyl-or aryl-substituted alkynyliodonium salts 305 and 306 (eqs 157 and 158).…”

“…This reaction (eq 2) is especially useful for the preparation of cyano(phenyl)iodonium triflate ( 8 , X = CN, R = CF 3 ), which is a highly efficient iodonium transfer reagent in the syntheses of various alkynyl and alkenyl(phenyl)iodonium salts. − …”

Heterocations in Superacid Systems

“…In each, one fluorine atom of the anion forms an almost linear but asymmetric CÀXerF contact (CÀXe bond lengths The xenodeborylation method has been extended to hydrogen-containing aryl compounds, in which the aryl group bears at least one electron-withdrawing substituent (F or CF 3 ). 1083 Alkynylxenonium salts have been obtained by Stang and co-workers 1084 (372) and Frohn and Bardin 1085,1086 (373). When the synthesis is carried out in the presence of BF 3 ÁOMe 2 , in turn, stable tetrafluoroborates are isolated.…”

“…Dence and Roberts 366 attempted to prepare the cyclopropylphenyliodonium ion from phenyliodoso chloride and cyclopropyllithium [Eq. Tributylstannanes have also been used in the synthesis of alkynyl(aryl)iodonium salts, including 1,3-diynyl derivatives 373 and the parent member of the family, HCCIPh þ TfO À , which was characterized by X-ray structure analysis. However, they were unable to obtain the corresponding iodonium ion or any cyclopropylbenzene from the reaction mixture.…”