Patent ID: 7868170

Claim:
A platinum complex of the following formula (I): wherein X is a counter ion; n is 0 or 1; X 1 and X 2 independently are C or N; R 1 , R 2 and R 3 independently are H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, R 1 is H and R 2 and R 3 together are or R 3 is H and R 1 and R 2 together are when X 1 is C; R 1 and R 3 independently are H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, and R 2 is omitted, when X 1 is N; R 4 is H and R 5 is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, or R 4 and R 5 together are C4-C8 alkylene or bridged carbocyclic C4-C12 alkylene, when X 2 is C; R 4 is omitted and R 5 is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, when X 2 is N; and L 1 and L 2 each are when n is 1, or together are when n is 0, wherein X 3 is C or N; R 6 and R 7 independently are H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl; R 8 is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl; X 4 and X 5 independently are C or N; each R′ independently is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl; X 6 and X 7 independently are C or N; R 9 is H and R 10 is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, or R 9 and R 10 together are C4-C8 alkylene or bridged carbocyclic C4-C12 alkylene, when X 6 is C; R 9 is omitted and R 10 is H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, when X 6 is N; R 11 , R 12 and R 13 independently are H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl, R 11 is H and R 12 and R 13 together are or R 13 is H and R 11 and R 12 together are when X 7 is C; and R 11 and R 13 independently are H, C1-C8 alkyl, phenyl, or C1-C4 perfluoroalkyl and R 12 is omitted, when X 7 is N.