Herbert M.B.,California Institute of Technology |
Marx V.M.,California Institute of Technology |
Pederson R.L.,Materia Inc. |
Grubbs R.H.,California Institute of Technology
Angewandte Chemie - International Edition | Year: 2013
Very short synthetic routes to nine cisolefin-containing pheromones containing a variety of functionality, including an unconjugated (E,Z) diene, are reported (see scheme). These lepidopteran pheromones are used extensively for pest control, and were easily prepared using ruthenium-based Z-selective cross metathesis, highlighting the advantages of this method over less efficient ways to form Z olefins. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Everson D.A.,University of Rochester |
Jones B.A.,University of Rochester |
Jones B.A.,Materia Inc. |
Weix D.J.,University of Rochester
Journal of the American Chemical Society | Year: 2012
A general method is presented for the synthesis of alkylated arenes by the chemoselective combination of two electrophilic carbons. Under the optimized conditions, a variety of aryl and vinyl bromides are reductively coupled with alkyl bromides in high yields. Under similar conditions, activated aryl chlorides can also be coupled with bromoalkanes. The protocols are highly functional-group tolerant (-OH, -NHTs, -OAc, -OTs, -OTf, -COMe, -NHBoc, -NHCbz, -CN, -SO 2Me), and the reactions are assembled on the benchtop with no special precautions to exclude air or moisture. The reaction displays different chemoselectivity than conventional cross-coupling reactions, such as the Suzuki-Miyaura, Stille, and Hiyama-Denmark reactions. Substrates bearing both an electrophilic and nucleophilic carbon result in selective coupling at the electrophilic carbon (R-X) and no reaction at the nucleophilic carbon (R-[M]) for organoboron (-Bpin), organotin (-SnMe 3), and organosilicon (-SiMe 2OH) containing organic halides (X-R-[M]). A Hammett study showed a linear correlation of σ and σ(-) parameters with the relative rate of reaction of substituted aryl bromides with bromoalkanes. The small ρ values for these correlations (1.2-1.7) indicate that oxidative addition of the bromoarene is not the turnover-frequency determining step. The rate of reaction has a positive dependence on the concentration of alkyl bromide and catalyst, no dependence upon the amount of zinc (reducing agent), and an inverse dependence upon aryl halide concentration. These results and studies with an organic reductant (TDAE) argue against the intermediacy of organozinc reagents. © 2012 American Chemical Society. Source
Materia Inc. and California Institute of Technology | Date: 2014-09-26
The invention provides novel organometallic complexes useful as olefin metathesis catalysts. The complexes have an N-heterocyclic carbene ligand and a chelating carbene ligand associated with a Group 8 transition metal center. The molecular structure of the complexes can be altered so as to provide a substantial latency period. The complexes are particularly useful in catalyzing ring closing metathesis of acyclic olefins and ring opening metathesis polymerization of cyclic olefins.
Materia Inc. | Date: 2014-09-09
Catalytic complexes including a metal atom having anionic ligands, at least one nucleophilic carbene ligand, and an alkylidene, vinylidene, or allenylidene ligand. The complexes are highly stable to air, moisture and thermal degradation. The complexes are designed to efficiently carry out a variety of olefin metathesis reactions.
Materia Inc. | Date: 2014-04-09
This invention describes processes to make products by cross metathesis of functionalized or non-functionalized olefins with poly-branched poly-olefins such as terpenes (e.g., farnesene(s), -farnesene, -farnesene, -myrcene, etc.) and compositions made by such methods. More particularly, the present invention relates to methods of making (i) cross metathesis products by a cross metathesis reaction between at least one hydrovinylated olefinic substrate and at least one hydrovinylated cross metathesis substrate in the presence of at least one olefin metathesis catalyst; (ii) cross metathesis products by a cross metathesis reaction between at least one hydrovinylated olefinic substrate and at least one cross metathesis substrate in the presence of at least one olefin metathesis catalyst; and (iii) cross metathesis products by a cross metathesis reaction between at least one olefinic substrate and at least one hydrovinylated cross metathesis substrate in the presence of at least one olefin metathesis catalyst; as well as compositions made by such methods.