1350. Polyfluorocycloalkenes. Part III. Reactions with alcohols under ionic conditions to give ethers

Abstract

Various polyfluoro-cyclic olefins have been treated with several alcohols in the presence of a base, and the ethers formed fully characterised. Each reaction, with one exception, gave two mono-alkoxy-olefins, one substituted in the vinylic position, the other in the allylic positioc, by what appears to be an addition-elimination pathway; the ratio of these ethers varied with the alcohol and olefin used. I n the characterisation of these olefinic ethers, potassium permanganate oxidation gave a number of new alkoxypolyfluorodibasic acids.View Article Online centred a t 4.5 (intensity ratio 1).Reaction of 2,2,3,3-TetrafEuoropropan-l-ol with Decafluorocyc1ohexene.-In the usual way (E 2.67 x lo3) (in ethanol).

Bis-perfluorocycloalkenyl (PFCA) aryl ether monomers towards a versatile class of semi-fluorinated aryl ether polymers

“…1). As expected, PFCAs react with various nucleophiles including phenoxides, [12][13][14][15] alkoxide, [16][17][18] organometallic, [19][20][21] amines, [22][23][24][25] thiols, 26 azoles 27 and phosphonium ylides. 28 PFCA derivatives have thus shown a variety of applications including photochromic small molecules, [29][30][31][32][33] nonlinear optical activity, 34 lubricants, 21 and etching agents.…”

Fluorinated cyclopropenes and cyclopropenium ions

“…A similar mechanism has been postulated to explain the nucleophilic attack of perhalocycloalkenes (having four, five and six carbons) by alkoxide ions. [16][17][18] On the basis of exchange reactions of various "haloforms,"16 the stabilization of carbanions by a substituents is in the order I ~Br > Cl > F > OEt while nmr studies20 have established the following order of "apparent electron-withdrawing power" for a substituents: I > Br > Cl > F » CF2Br > CF2C1 > CF3. The attack on 4 or 9 by fluoride would necessarily be directed exclusively at the fluorine-carrying trigonal carbon because the developing negative charge could be stabilized by the chlorine or bromine at the adjacent carbon.…”

Reactions of 1,2-dichloroperfluorocycloalkenes and perfluorocycloalkenes with various trivalent phosphines

“…Recent studies indicate that once the initial carbanion is formed elimination can occur at two different sites. 19,20 The mode of elimination depends on the effect which the a substituents have on the stability of the carbanion.9,21 In our studies, the elimination of the halogen vicinal to the phosphorus atom appears to be the predominant leaving group. This is actually what one would predict.…”