Organometallic ruthenium complexes and related methods for the preparation of tetra-substituted and other hindered olefins

An N-heterocyclic carbene (NHC) ruthenium olefin metathesis catalyst of formula (I):

• wherein:
• X1 and X2 are independently anionic ligands;
• n is 0, 1 or 2;
• R9 and R10 are each independently hydrogen or a substituted or unsubstituted substituent selected from the group consisting of C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, aryl, C1-C20 carboxylate, C1-C20 alkoxy, C2-C20 alkenyloxy, C2-C20 alkynyloxy, aryloxy, C2-C20 alkoxycarbonyl, C1-C20 alkylthio, C1-C20 alkylsulfonyl and C1-C20 alkylsulfinyl;
• or R9 and R10 may optionally be linked together to form a cyclic structure via one of the listed substituents;
• m is 1 or 2;
• when m is 1, L is a neutral 2-electron donor ligand and may optionally be linked to R10 forming a chelating carbene ligand when n is zero;
• when m is 2, L is a heteroarene ligand;
• and
• NHC is an N-heterocyclic carbene ligand selected from formulas (III)-(V):
• wherein
• R1, R2, and R3 are either:
• a) each R1 is independently a primary or secondary C1-C4 alkyl group;
• each R2 is independently H, a substituted or unsubstituted C1-C10 alkyl group, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted anthracenyl;
• and each R3 is independently H, a substituted or unsubstituted C1-C8 alkyl group, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted anthracenyl, or a functional group selected from the group consisting of halo, hydroxyl, sulfhydryl, cyano, cyanato, thiocyanato, amino, nitro, nitroso, sulfo, sulfonato, boryl, borono, phosphono, phosphonato, phosphinato, phospho, phosphino, and silyloxy;
• or
• b) R1 is H;
• each R2 is independently H, a substituted or unsubstituted C1-C8 alkyl group, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted anthracenyl;
• and each R3 is independently H, a substituted or unsubstituted C1-C8 alkyl group, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted anthracenyl or a functional group selected from the group consisting of halo, hydroxyl, sulfhydryl, cyano, cyanato, thiocyanato, amino, nitro, nitroso, sulfo, sulfonato, boryl, borono, phosphono, phosphonato, phosphinato, phospho, phosphino, and silyloxy;
• with the provisos that both R2 substituents on the same phenyl ring are not H;
• R4 and R6 are each independently H, a substituted or unsubstituted C1-C8 alkyl group, substituted or unsubstituted aryl, or in formulas (III) and (V), together with the carbons carrying them, form a substituted or unsubstituted, fused 4-8 membered carbocylic ring or a substituted or unsubstituted, fused aromatic ring;
• R5 and R7 are independently H, a substituted or unsubstituted C1-C8 alkyl group;
• and
• R8 is a C1-C12 alkyl or a C3-C12 cycloalkyl.