Asymmetric induction in cyclopropanation with homogeneous and immobilized chiral metal β-diketonate catalysts

Abstract

Copper complexes of 3-trifluoroacetyl-( +)-camphor and two of its derivatives give high optical yields when used as catalysts for the asymmetric cyclopropanation of styrene with 2-diazodimedone; an immobilised analogue of these homogeneous catalysts retains high activity, is readily recovered, and has potential for recycling.

Silica Supported Rhodium Metal Nanoparticles Stabilized With (-)-Diop. Effect of Ligand Concentration and Metal Loading on the Enantioselective Hydrogenation of Ketones

“…Nowadays important efforts have focused toward the "heterogenization" of the homogeneous asymmetric catalysis or to develop strategies to immobilize chiral NPs on solid supports to achieve simpler and more efficient catalysts able to be used in consecutive cycles and ideally in continuous processes [4][5][6] .…”

Selectivity in cyclopropanations and 1,3-cycloadditions in transition metal-catalyzed decompositions of 2-diazocyclohexane-1,3-diones and the corresponding phenyliodonium ylides

“…Cyclopropanation of styrene and apolar terminal olefins The conditions of Matlin et al 10 for cycloproanation of styrene consist in heating styrene neat or in toluene to reflux in the presence of 1a and the appropriate Cu-catalyst. In our hands, these reaction conditions resulted in complete polymerization of styrene, and no cyclopropane could be isolated.…”

“…The readily avaliable [Cu{(+)-facam} 2 ] produced the cyclopropane in 36% yield and with 91.7% ee. 10 However, details of the procedure have not been published, and the reported results have met some scepticisme. …”

Synthesis and Reduction of 10-Phthalimidocamphor Oxime

“…The unique reactivity of camphor enables its derivatization at positions 2, 3, 4, 5, 8-10, as well as selective cleavage of the C1-C2 and C2-C3 bonds ( Figure 1). 1,2 All of the above makes camphor a very desirable starting compound for the preparation of a wide variety of products 3 ranging from natural products 1,2 to chiral auxiliaries, 4,5 ligands in asymmetric synthesis, [6][7][8][9][10] organocatalysts, 11 and NMR shift reagents. 12 Within our continuing study on camphor-based diamines as potential organocatalyst scaffolds, [13][14][15] we recently reported on the synthesis of a novel type of 1,3-diamine-derived bifunctional squaramide orga nocatalysts A prepared from 10-iodocamphor and their application as highly efficient catalysts in Michael additions of 1,3-dicarbonyl nucleophiles to trans-β-nitrostyrenes.…”