A method of producing an activated substrate, the method comprising: (a) modifying a substrate comprising a base matrix to form a base matrix comprising a leaving group, wherein modifying the substrate comprises: (ai) contacting the substrate with an electrophile to form a base matrix comprising an unsaturated hydrocarbon chain, wherein the electrophile is a compound of formula: R 1 -L 1 -X 1 -L 2 -R 2, wherein R 1 is an optionally substituted 3 to 6 membered heterocyclic ring; R 2 is an optionally substituted C 2 -C 12 alkenyl or an optionally substituted C 2 -C 12 alkynyl; L 1 and L 2 are each independently absent, an optionally substituted C 1-12 alkylene, an optionally substituted C 2-12 alkenylene or an optionally substituted C 2-12 alkynylene, where the backbone of the alkylene, alkenylene or alkynlene is optionally interrupted by one or more heteroatoms; X 1 is NR 3, O or S; and R 3 is H, an optionally substituted C 1 -C 6 alkyl, an optionally substituted C 2 -C 6 alkenyl or an optionally substituted C 2 -C 6 alkynyl; (aii) contacting the base matrix formed in step (ai) with a halogenating agent, to provide a halogenated base matrix; (b) contacting the base matrix formed in step (aii) with an aminating agent, to thereby provide an aminated base matrix; and (c) contacting the aminated base matrix formed in step (b) with a heteroaromatic compound, wherein the heteroaromatic compound is a 5 to 12 membered heteroaromatic ring substituted with at least two halogens and optionally one or more further substituents, to produce an activated substrate. (a) modifying a substrate comprising a base matrix to form a base matrix comprising a leaving group, wherein modifying the substrate comprises: (ai) contacting the substrate with an electrophile to form a base matrix comprising an unsaturated hydrocarbon chain, wherein the electrophile is a compound of formula: R 1 -L 1 -X 1 -L 2 -R 2, wherein R 1 is an optionally substituted 3 to 6 membered heterocyclic ring; R 2 is an optionally substituted C 2 -C 12 alkenyl or an optionally substituted C 2 -C 12 alkynyl; L 1 and L 2 are each independently absent, an optionally substituted C 1-12 alkylene, an optionally substituted C 2-12 alkenylene or an optionally substituted C 2-12 alkynylene, where the backbone of the alkylene, alkenylene or alkynlene is optionally interrupted by one or more heteroatoms; X 1 is NR 3, O or S; and R 3 is H, an optionally substituted C 1 -C 6 alkyl, an optionally substituted C 2 -C 6 alkenyl or an optionally substituted C 2 -C 6 alkynyl; (aii) contacting the base matrix formed in step (ai) with a halogenating agent, to provide a halogenated base matrix; (ai) contacting the substrate with an electrophile to form a base matrix comprising an unsaturated hydrocarbon chain, wherein the electrophile is a compound of formula: R 1 -L 1 -X 1 -L 2 -R 2, wherein R 1 is an optionally substituted 3 to 6 membered heterocyclic ring; R 2 is an optionally substituted C 2 -C 12 alkenyl or an optionally substituted C 2 -C 12 alkynyl; L 1 and L 2 are each independently absent, an optionally substituted C 1-12 alkylene, an optionally substituted C 2-12 alkenylene or an optionally substituted C 2-12 alkynylene, where the backbone of the alkylene, alkenylene or alkynlene is optionally interrupted by one or more heteroatoms; X 1 is NR 3, O or S; and R 3 is H, an optionally substituted C 1 -C 6 alkyl, an optionally substituted C 2 -C 6 alkenyl or an optionally substituted C 2 -C 6 alkynyl;, wherein R 1 is an optionally substituted 3 to 6 membered heterocyclic ring; R 2 is an optionally substituted C 2 -C 12 alkenyl or an optionally substituted C 2 -C 12 alkynyl; L 1 and L 2 are each independently absent, an optionally substituted C 1-12 alkylene, an optionally substituted C 2-12 alkenylene or an optionally substituted C 2-12 alkynylene, where the backbone of the alkylene, alkenylene or alkynlene is optionally interrupted by one or more heteroatoms; X 1 is NR 3, O or S; and R 3 is H, an optionally substituted C 1 -C 6 alkyl, an optionally substituted C 2 -C 6 alkenyl or an optionally substituted C 2 -C 6 alkynyl; (aii) contacting the base matrix formed in step (ai) with a halogenating agent, to provide a halogenated base matrix; (b) contacting the base matrix formed in step (aii) with an aminating agent, to thereby provide an aminated base matrix; and (c) contacting the aminated base matrix formed in step (b) with a heteroaromatic compound, wherein the heteroaromatic compound is a 5 to 12 membered heteroaromatic ring substituted with at least two halogens and optionally one or more further substituents, to produce an activated substrate.