478623-08-4Relevant articles and documents
Low catalyst loading in ring-closing metathesis reactions
Kadyrov, Renat
, p. 1002 - 1012 (2013/02/23)
An efficient procedure is described for ring-closing metathesis reactions. A conversion of 95 % for diethyl diallylmalonate in dilute solution could be achieved within a few minutes, reaching TOF=4173min-1, with very low loading of commercially available Ru catalysts that contained unsaturated NHC ligands. In general, only 50 to 250ppm of the catalyst is required to achieve near-quantitative conversion into a broad variety of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-tert-butoxycarbonyl (N-Boc)- and N-para-toluenesulfonyl (N-Ts)-protected cyclic amines and 9-16-membered lactones. The synthesis of macrocyclic proline-based lactams required slightly higher catalyst loadings. Along with monocyclic products, oligomeric byproducts, mostly cyclodimers, were isolated and characterized. Getting some closure: An efficient procedure is described for ring-closing metathesis reactions in which only 50 to 250ppm of catalyst is required to effect almost-quantitative conversion into a broad range of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-protected cyclic amines, 9-16-membered lactones, and 11-16-membered proline-based lactams. Copyright
Synthesis of glycerol homologues
Thota, Kiran Kumar,Trudell, Mark L.
, p. 2280 - 2286 (2013/09/02)
A series of monoprotected glycerol homologues and triols were prepared in high overall yields (>90%) via the hydroboration-oxidation of the corresponding dienols. Hydroboration with disiamylborane and concomitant alkaline oxidation (NaOH, H2O2) was found to be a mild, high-yielding, and highly efficient method for the construction of a variety of glycerol homologues. Georg Thieme Verlag Stuttgart. New York.
Relative rate profile for ring-closing metathesis of a series of 1-substituted 1,7-octadienes as promoted by a 4,5-dihydroimidazol-2-ylidene-coordinated ruthenium catalyst
Guo, Xin,Basu, Kallol,Cabral, Jose A.,Paquette, Leo A.
, p. 789 - 792 (2007/10/03)
(Matrix presented) This report details the kinetic responses of nine compounds of type 6 to ring-closing metathesis as promoted by 2 to give the identical product 7. The experimental observations have been subjected to Hammett analysis. The ρ value for the composite aromatic derivatives (R = p-XC6H4-) differs from that of the aliphatic series, although both are negative because electron-donating groups accelerate the reaction.
