5202-80-2Relevant academic research and scientific papers
Regioselective Rh(I)-catalyzed sequential hydrosilylation toward the assembly of silicon-based peptidomimetic analogues
Min, Geanna K.,Skrydstrup, Troels
experimental part, p. 5894 - 5906 (2012/09/21)
A highly regioselective Rh(I)-catalyzed hydrosilylation of enamides is presented. This mild protocol allows access to a wide variety of different arylsilanes with substitution at the β-position of the enamide and functionalization on the alkyl chain tethered to the silane. This protocol is extended to include a sequential one-pot hydrosilylation. Using diphenylsilane as the appendage point, hydrosilylation of a protected allyl alcohol followed by hydrosilylation of an enamide generates a complex organosilane in one step. This highly convergent strategy to synthesize these functionalized systems now provides a way for the rapid assembly of a diverse collection of silane-based peptidomimetic analogues.
Enantioselective hydroformylation of N-vinyl carboxamides, allyl carbamates, and allyl ethers using chiral diazaphospholane ligands
McDonald, Richard I.,Wong, Gene W.,Neupane, Ram P.,Stahl, Shannon S.,Landis, Clark R.
supporting information; body text, p. 14027 - 14029 (2011/01/04)
Rhodium complexes of diazaphospholane ligands catalyze the asymmetric hydroformylation of N-vinyl carboxamides, allyl ethers, and allyl carbamates; products include 1,2- and 1,3-aminoaldehydes and 1,3-alkoxyaldehydes. Using glass pressure bottles, short reaction times (generally less than 6 h), and low catalyst loading (commonly 0.5 mol %), 20 substrates are successfully converted to chiral aldehydes with useful regioselectivity and high enantioselectivity (up to 99% ee). Chiral Roche aldehyde is obtained with 97% ee from the hydroformylation of allyl silyl ethers. Commonly difficult substrates such as 1,1- and 1,2-disubstituted alkenes undergo effective hydroformylation with 89-97% ee and complete conversion for six examples. Palladium-catalyzed aerobic oxidative amination of allyl benzyl ether followed by enantioselective hydroformylation yields the β3-aminoaldehyde with 74% ee.
