Patent ID: 7208638

Claim:
A process of preparing (per)fluorohalogenethers having general formula: wherein: A and A′, equal to or different from each other, are selected among Cl, Br and H, with the proviso that A and A′ are not contemporaneously equal to H; m=1 or 2; n=0 or 1; with the proviso that when m=2, n=0 and when m=1, n=1; R′ is a (per)fluoroalkyl substituent containing from 1 to 3 carbon atoms; X 1 =F or CF 3; z=0or 1; z′ =0 or 1; R is a (per)fluoropolyether substituent having formula -R f T, wherein T has the following meanings: wherein A, A′, R′, m, n, X 1 , z and z′ are as above; X 1 CFX 1 (CF2) z (CH 2 ) z ,— wherein X 1 =F, CF 3 , Cl; X 1 , z and z′ are as above; wherein R′ and n are as above; X 1 , z and z′ are as above; q=0, 1 with the proviso that when q=0 then n=1; when q=1 then n=0; R f is a (per)fluorooxyalkylene chain containing one or more of the following units statistically distributed along the chain: (C 3 F 6 O); (CFX 1 O) wherein X 1 is F or CF 3 ; (C 2 F 4 O); (CF 2 (CF 2 ) x ′ CF 2 O) wherein x′ is an integer equal to 1 or 2; (CR 4 R 5 CF 2 CF 2 O) wherein R 4 and R 5 are equal to or different the one from the other and are selected between H, Cl, and one fluorine atom of the perfluo-romethylene unit can optionally be substituted with H, Cl or (per)fluoroalkyl having, for example, from 1 to 4 carbon atoms; by reaction of carbonyl compounds having formula: (R′) n —C(O)(F) q (CFX 1 (CF 2 ) z (CH 2 ) z′ OR 1 ) (II) wherein: R′, n, X 1 , z and z′ are as above; q=0, 1; R 1 is a (per)fluoropolyether substituent -R f T 1 wherein: R f is as above, T 1 has the following meanings: X 1 CFX 1 (CF 2 ) z (CH 2 ) z′ —, wherein X l X 1 , z and z′ are as above, (R′) n —C(O)(F) q —CFX 1 (CF 2 ) z (CH 2 ) z′ — wherein: R′, n, q, X 1 , z and z′ are as above; with the proviso that when q=0 then n=1; when q=1 then n=0; in liquid phase, with elemental fluorine and with olefinic compounds of formula: CAF=CA′F 2 (III) wherein A and A′ are as above, at temperatures from −120° C. to −20° C., optionally in the presence of an inert solvent under the reaction conditions.