ChemInform Abstract: Phenyl‐α,α,ω‐trihydropolyfluoroalkyliodonium Borofluorides.

Abstract

ChemInform Abstract In the presence of BF3 the reaction between the difluoroiodotrihydropolyfluoroalkanes (I) and benzene (II) affords the title compounds (III). Their perfluoro analogues are known to be strong perfluoroalkylating agents. For a comparison, the alkylating properties of the title compounds (III) with a methylene bridge between the aryliodonium moiety and the polyfluoroalkyl group are investigated. In the reaction of (IIIa) with p-chlorothiophenol (IV) the perfluoroalkyl group adds to the sulfur atom to give the product (V). The reaction with pyridine (VI) proceeds via addition of the polyfluoroalkyl group to the nitrogen atoms to give the quaternary pyridinium salt (VII). In the reaction of (IIIb) with N,N-dimethylaniline (VIII) the main product is the quaternary salt (IX) accompanied by the p-polyfluoroalkyl derivative (X).

Electrophilic Perfluoroalkylating Agents

“…61 In contrast to FMITS (Table 12, run 3) which produced only the N-polyfluoroalkylated product 129 (R f ′ ) CF 3 ), the tetrafluoroborate reagent 127 produced both N-and C-polyfluoroalkylated products 129 and 130 (R f ′ ) (CF 2 CF 2 ) 2 H) (eq 39). 61 The dependence of the products' identities on the counteranins -OTf and BF 4is noteworthy. However, FITS did produce a small amount of the C-dihydroperfluoroalkylated product in addition to the O-dihydroperfluoroalkylated prod-uct when reacted with lithiun salts of more active phenol derivatives.…”

“…In contrast to (2,2,2trifluoroethyl)phenyliodonium triflate (FMITS-1) which was synthesized in high yield, 57 (2,2,2-trifluoroethyl)phenyliodonium tetrafluoroborate could not be synthesized by the same method as 127 and 128. 61 (1,1,3-Trihydrotetrafluoropropyl)phenyliodonium tetrafluoroborate could not be synthesized. 61 The FITS and FMITS reagents were compared by thermolysis.…”

“…61 (1,1,3-Trihydrotetrafluoropropyl)phenyliodonium tetrafluoroborate could not be synthesized. 61 The FITS and FMITS reagents were compared by thermolysis. 57b Thermolysis of the FITS reagent gave three products, the R f -triflate 131, iodobenzene, and the R f -iodobenzene 132.…”

Exploration of fluorination reagents starting from FITS reagents

“…They failed in synthesizing (2,2,2-trifluoroethyl)phenyliodonium tetrafluoroborate [38]. Unfortunately, we failed to synthesize the trifluoromethyl analog (FITS-1) because of the abnormality of CF 3 group.…”

“…Yagupolskii et al [38] reported the synthesis of (a, a, vtrihydroperfluoroalkyl)phenyliodonium tetrafluoroborates and a, a, v-trihydroperfluoroalkylation of some substrates with them.…”