Synthesis of Terminal Alkenes From Internal Alkenes Via Olefin Metathesis

A method for synthesizing a terminal olefin, the method comprising:

• contacting, in the presence of a ruthenium alkylidene metathesis catalyst, an olefinic substrate comprised of at least one internal olefin with an alpha olefin having at least 3 carbon atoms, under reaction conditions effective to allow cross-metathesis to occur, wherein the ruthenium alkylidene metathesis catalyst has the structure of formula (IV):
• wherein:
• M is ruthenium;
• n is 0 or 1;
• m is 0, 1, or 2;
• L2 and L3 are neutral electron donor ligands;
• X1 and X2 are anionic ligands;
• R1 and R2 are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups;
• X and Y are heteroatoms selected from N, O, S, and P;
• p is zero when X is O or S, and p is 1 when X is N or P;
• q is zero when Y is O or S, and q is 1 when Y is N or P;
• Q1, Q2, Q3, and Q4 are independently selected from hydrocarbylene, substituted hydrocarbylene, heteroatom-containing hydrocarbylene, substituted heteroatom-containing hydrocarbylene, and —(CO)—, and further wherein two or more substituents on adjacent atoms within Q may be linked to form an additional cyclic group;
• w, x, y, and z are independently zero or 1;
• and
• R3, R3A, R4, and R4A are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl,
• wherein any two or more of X1, X2, L2, L3, R1, R2, R3, R3A, R4, and R4A can be taken together to form a cyclic group, and further wherein any one of X1, X2, L2, L3, R1, R2, R3, R3A, R4, and R4A can be attached to a support.