Tethered alkylidene and methods of making the same

A compound having a structure represented by formula (I) or formula (II):

• wherein the dashed lines are optional double bonds;
• M is a transition metal;
• Q is a neutral or anionic ligand;
• each X is independently selected from S, O, NR5, N(R5)2, P(R6)2, C(R7)2, BR11, Si(R12)2, Se, and Te;
• each X′ is independently selected from S, O, N, NR5, P, PR6, CR7, B, SiR12, Se, and Te;
• wherein the curved line, together with each X′ and M, form a metallacycle and the curved line represents a chain of 1 to 6 atoms independently selected from C, O, N, and S;
• each R1 is independently selected from H, C1-C20haloalkyl, C1-C20alkyl, C2-C20alkenyl, C4-C20cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• each R2 is independently selected from H, C1-C22 alkyl, C4-C8 cycloalkyl, and Ar1;
• each R3 is independently selected from H, C1-C20haloalkyl, C1-C20alkyl, C2-C20alkenyl, C4-C20cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, or two vicinal R3 together with the carbon atoms to which they are attached, form a five- to eight-member cycloalkyl, aryl, heteroaryl, or heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• each R4 is independently selected from a bond, —C(R2)2—, or —C(R2)2C(R2)2—
• each R5 is independently selected from C1-C22 alkyl, C4-C10 cycloalkylC4-C8cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, or two vicinal R5 together with the atoms to which they are attached, form a five- to eight-member cycloalkyl, aryl, heteroaryl, or heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• each R6 is independently selected from C1-C22 alkyl, C4-C8 cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, or two vicinal R6 together with the atoms to which they are attached, form a five- to eight-member cycloalkyl, aryl, heteroaryl, or heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• each R7 is independently selected from H, C1-C22 alkyl, C4-C8cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, or two vicinal R7 together with the atoms to which they are attached, form a five- to eight-member cycloalkyl, aryl, heteroaryl, or heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• and,
• each R11 and R12 are independently selected from C1-C22alkyl, C4-C8cycloalkyl, Ar1, C1-C20heteroalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, and C1-C20heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S, or two vicinal R11, or two vicinal R12 together with the atoms to which they are attached, form a five- to eight-member cycloalkyl, aryl, heteroaryl, or heterocycloalkyl comprising 1 to 5 heteroatoms selected from O, N, and S;
• each Ar1 is independently selected from C6-C22 aryl and a 5-12 membered heteroaryl comprising from 1 to 3 ring heteroatoms selected from O, N, and S.