Synthesis of Molybdenum and Tungsten Alkylidene Complexes That Contain Sterically Demanding Arenethiolate Ligands

• Main Authors: Hoveyda, Amir H. (Author), Townsend, Erik M. (Contributor), Hyvl, Jakub (Contributor), Forrest Jr, William P (Contributor), Schrock, Richard Royce (Contributor), Mueller, Peter (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Chemistry (Contributor)
• Format: Article
• Language: English
• Published: American Chemical Society (ACS), 2017-05-26T14:08:20Z.
• Subjects: Article
• Online Access: Get fulltext

Imido alkylidene complexes of Mo and W and oxo alkylidene complexes of W that contain thiophenoxide ligands of the type S-2,3,5,6-Ph[subscript 4]C[subscript 6]H (STPP) and S-2,6-(mesityl)[subscript 2]C[subscript 6]H[subscript 3] (SHMT = S-hexamethylterphenyl) have been prepared in order to compare their metathesis activity with that of the analogous phenoxide complexes. All thiolate complexes were significantly slower (up to ∼10× slower) for the metathesis homocoupling of 1-octene or polymerization of 2,3-dicarbomethoxynorbornene, and none of them was Z-selective. The slower rates could be attributed to the greater σ-donating ability of a thiophenoxide versus the analogous phenoxide and consequently a higher electron density at the metal in the thiophenoxide complexes.
National Institutes of Health (U.S.) (Grant GM-59426)