Sulfur-containing additives for electrochemical or optoelectronic devices

A compound of formula I

• [K—(CH2)—(CH2)u—SO3—(CH2)v—R″]+[A]− I,
• wherein
• u is 0, 1, 2, 3, 4, 5, 6 or 7 and where a CH2 group of the —(CH2)u— alkylene chain may be replaced by O or may have a double bond,
• v is 0, 1, 2, 3 or 4,
• —SO3— is
• R″ independently at each occurrence is a straight-chain or branched alkyl group having 1 to 20 C atoms, and may be unfluorinated, partly fluorinated or fully fluorinated, or is a straight-chain or branched alkenyl group having 2 to 20 C atoms and a double bond, a straight-chain or branched alkynyl group having 2 to 20 C atoms and a triple bond, or an aryl group having 6 to 12 C atoms, which group may be singly or multiply substituted by at least one selected from the group consisting of F, Cl, and a straight-chain or branched, partly fluorinated or fully fluorinated alkyl group having 1 to 8 C atoms,
• K is a cation selected from the group consisting of
• R3N+—*, R3P+—*,
• wherein
• R independently at each occurrence is methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl or tert-butyl, wherein optionally a CH2 group, not directly joined to N or P, in the radicals R is replaced by O,
• Y is CH2, O, S or NR′,
• R′ is methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl or tert-butyl,
• A is an anion selected from the group consisting of
• [FzB(CmF2m+1)4-z]−,
• [FyP(CmF2m+1)6-y]−,
• [(CmF2m+1)2P(O)O]−,
• [CmF2m+1P(O)O2]2−,
• [(O—C(O)—CmF2m+1]−,
• [N(C(O)—CmF2m+1)2]−,
• [N(S(O)2—CmF2m+1)2]−,
• [N(C(O)—CmF2m+1)(S(O)2—CmF2m+1)]−,
• [N(C(O)—CmF2m+1)(C(O)F)]−,
• [N(S(O)2—CmF2m+1)(S(O)2F)]−,
• [N(S(O)2F)2]−,
• [C(C(O)—CmF2m+1)3]−,
• [C(S(O)2—CmF2m+1)3]−,
• [O—S(O)2—CmF2m+1]−,
• m is 1, 2, 3, 4, 5, 6, 7 or 8, wherein optionally CF2 groups in the anions are replaced by O, S(O)2, NR or CH2,
• z is 1, 2 or 3,
• y is 1, 2, 3, 4, 5 or 6,
• X is B or Al,
• R1 and R2 are each independently of one another F, Cl, Br, I, a straight-chain or branched perfluoroalkyl group having 1 to 20 C atoms, a straight-chain or branched alkoxy group having 1 to 20 C atoms, which may be unfluorinated, partly fluorinated or fully fluorinated, or —O—C(O)-alkyl, where alkyl is a straight-chain or branched alkyl group having 1 to 20 C atoms, and may be unfluorinated, partly fluorinated or perfluorinated,
• and
• where
• independently at each occurrence is a bidentate radical which derives from a 1,2- or
• 1,3-diol, from a 1,2- or 1,3-dicarboxylic acid or from a 1,2- or 1,3-hydroxycarboxylic acid, by entering of pairs of adjacent OH groups in the compound into one bond each to the central atom X, accompanied by formal elimination of two H atoms,
• wherein an electroneutrality of a corresponding salt thereof is observed.