Phosphonate based lithium complexes

A complex compound, wherein the complex compound satisfies formula (I):

• wherein R1 is selected from H, F, R2, OR2, OSi(R3R4R5), and O—X−Li+;
• wherein R2 is selected from C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C5-C7 (hetero)aryl, and C6-C13 (hetero)aralkyl, which may be substituted by one or more substituents selected from OSi(CH3)3 and F;
• R3, R4, and R5 are independently from each other selected from H, F, R2, OR2, and OSi(R6)3;
• and
• R6 is independently at each occurrence selected from H, F, R2 and OR2;
• and
• X is selected from Y1(R7)4-b and Y2(R8)6-b;
• wherein Y1 is B or Al;
• Y2 is P, Sb, or As;
• if X is Y1(R7)4-b, then b is an integer from 1 to 4;
• if X is Y2(R8)6-b then b is an integer from 1 to 6;
• and
• R7 and R8 are independently at each occurrence selected from F, R9, and OR9;
• wherein R9 is selected from C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C5-C7 (hetero)aryl, and C6-C13 (hetero)aralkyl, which may be substituted by one or more F;
• one pair of R7 or one or two pairs of R8 may be combined and jointly be
• forming a cycle with Y1 or Y2, respectively;
• wherein
• is a bidentate radical derived from a 1,2-, 1,3- or 1,4-diol, from a 1,2-, 1,3- or 1,4-dicarboxylic acid or from a 1,2-, 1,3- or 1,4-hydroxycarboxylic acid;
• and
• R1 may be combined with one of R7 or R8, respectively, and jointly form a cycle.