A metal complex of formula (I) wherein M is iridium; L 1 and L 2 are independently selected from: a halogen, a nitrile, an amine, a phosphine, a phosphite, a sulfonate ester, a N-heterocyclic carbene or a 5 or 6 membered heterocyclic ring or L 1 and L 2 taken together are a bidentate ligand selected from: a diamine, a diphosphine, a diphosphite, a disulfonate ester, an amino acid, an amino alcohol, aminosulfonamides, an N-heterocyclic carbene, a diketonate and substituted or unsubstituted bipyridine, wherein L 1 and L 2 groups are unsubstituted or optionally substituted by halo, C 1-4 alkyl, C 1-4 haloalkyl, -OR A , -NR A R B , -CN, -SO 2 R A ; R 1 and R 2 are each independently represented by H, or unsubstituted: C 1-14 alkyl, C 1-14 haloalkyl, C 3-8 carbocyclic, and a 3 to 8 membered heterocyclic ring, C 1-14 alkyl substituted with phenyl, fluorous tag, or a solid support, or R 1 and R 2 together form a 3 to 8 membered heterocyclic ring; R 3 and R 4 are each independently selected from: H, halo, C 1-6 alkyl, C 1-6 haloalkyl, C 3-6 cycloalkyl, phenyl, a 5 or 6 membered heteroaryl ring and -OR A1 ; or R 3 and R 4 along with the shared, adjacent or non-adjacent carbon atoms to which they are attached together form a 3 to 8 membered carbocyclic ring (optionally a 5 or 6 membered carbocyclic ring), or one of R 1 and R 2 and one of R 3 and R 4 , together with the atoms to which they are attached, form a 3 to 8 membered heterocyclic ring; R 5 is selected from halo, C 1-6 alkyl, C 1-6 haloalkyl and C 3-6 cycloalkyl, C 6 aryl or 5 or 6 membered heteroaryl or two adjacent R 5 groups, together with the atoms to which they are attached, form a 5 or 6 membered carbocyclic ring; p is 0 or 1 or more; n is selected from 1 to 10; m is selected from 0, 1, 2, 3 or 4; R A , R B and R A1 are at each occurrence independently selected from: H, C 1-6 alkyl or C 1-6 haloalkyl. M is iridium; L 1 and L 2 are independently selected from: a halogen, a nitrile, an amine, a phosphine, a phosphite, a sulfonate ester, a N-heterocyclic carbene or a 5 or 6 membered heterocyclic ring or L 1 and L 2 taken together are a bidentate ligand selected from: a diamine, a diphosphine, a diphosphite, a disulfonate ester, an amino acid, an amino alcohol, aminosulfonamides, an N-heterocyclic carbene, a diketonate and substituted or unsubstituted bipyridine, wherein L 1 and L 2 groups are unsubstituted or optionally substituted by halo, C 1-4 alkyl, C 1-4 haloalkyl, -OR A , -NR A R B , -CN, -SO 2 R A ; R 1 and R 2 are each independently represented by H, or unsubstituted: C 1-14 alkyl, C 1-14 haloalkyl, C 3-8 carbocyclic, and a 3 to 8 membered heterocyclic ring, C 1-14 alkyl substituted with phenyl, fluorous tag, or a solid support, or R 1 and R 2 together form a 3 to 8 membered heterocyclic ring; R 3 and R 4 are each independently selected from: H, halo, C 1-6 alkyl, C 1-6 haloalkyl, C 3-6 cycloalkyl, phenyl, a 5 or 6 membered heteroaryl ring and -OR A1 ; or R 3 and R 4 along with the shared, adjacent or non-adjacent carbon atoms to which they are attached together form a 3 to 8 membered carbocyclic ring (optionally a 5 or 6 membered carbocyclic ring), or one of R 1 and R 2 and one of R 3 and R 4 , together with the atoms to which they are attached, form a 3 to 8 membered heterocyclic ring; R 5 is selected from halo, C 1-6 alkyl, C 1-6 haloalkyl and C 3-6 cycloalkyl, C 6 aryl or 5 or 6 membered heteroaryl or two adjacent R 5 groups, together with the atoms to which they are attached, form a 5 or 6 membered carbocyclic ring; p is 0 or 1 or more; n is selected from 1 to 10; m is selected from 0, 1, 2, 3 or 4; R A , R B and R A1 are at each occurrence independently selected from: H, C 1-6 alkyl or C 1-6 haloalkyl. <EOS>