304459-85-6Relevant articles and documents
Chiral-anion-dependent inversion of diastereo- and enantioselectivity in carbonyl crotylation via ruthenium-catalyzed butadiene hydrohydroxyalkylation
McInturff, Emma L.,Yamaguchi, Eiji,Krische, Michael J.
supporting information, p. 20628 - 20631 (2013/02/23)
The ruthenium catalyst generated in situ from H2Ru(CO)(PPh 3)3, (S)-SEGPHOS, and a TADDOL-derived phosphoric acid promotes butadiene hydrohydroxyalkylation to form enantiomerically enriched products. Notably, the observed diastereo- and enantioselectivity is the opposite of that observed using BINOL-derived phosphate counterions in combination with (S)-SEGPHOS, the same enantiomer of the chiral ligand. Match/mismatch effects between the chiral ligand and the chiral TADDOL-phosphate counterion are described. For the first time, single-crystal X-ray diffraction data for a ruthenium complex modified by a chiral phosphate counterion are reported.
Enhanced anti-diastereo- and enantioselectivity in alcohol-mediated carbonyl crotylation using an isolable single component iridium catalyst
Gao, Xin,Townsend, Ian A.,Krische, Michael J.
supporting information; scheme or table, p. 2350 - 2354 (2011/05/30)
The cyclometalated iridium complex (S)-I derived from [Ir(cod)Cl] 2, 4-cyano-3-nitrobenzoic acid, allyl acetate, and (S)-SEGPHOS is conveniently isolated by precipitation or through conventional silica gel flash chromatography. This single-component precatalyst allows alcohol mediated carbonyl crotylations to be performed at significantly lower temperature, resulting in enhanced levels of anti-diastereo- and enantioselectivity. Most significantly, the chromatographically isolated precatalyst (S)-I enables carbonyl crotylations that are not possible under previously reported conditions involving in situ generation of (S)-I.
Anti-diastereo-and enantioselective carbonyl crotylation from the alcohol or aldehyde oxidation level employing a cyclometallated iridium catalyst: α-methyl allyl acetate as a surrogate to preformed crotylmetal reagents
Kim, In Su,Han, Soo Bong,Krische, Michael J.
supporting information; experimental part, p. 2514 - 2520 (2009/08/16)
Under the conditions of transfer hydrogenation employing an ortho-cyclometallated iridium catalyst generated in situ from [Ir(cod)Cl] 2, 4-cyano-3-nitrobenzoic acid and the chiral phosphine ligand (S)-SEGPHOS, α-methyl allyl acetate couples to
