Optically pure (R) allylic alcohols and (R) 4-phenylbutan-2-ols were prepared via oxidative kinetic resolution using whole cells of Candida papapsilosis ATCC 7330.
Enantioselective addition of diethylzinc to aldehydes catalyzed by titanium(IV) complexes of N-sulfonylated amino alcohols with two stereogenic centers
作者:Jing-Song You、Ming-Yuan Shao、Han-Mou Gau
DOI:10.1016/s0957-4166(01)00522-5
日期:2001.11
Bidentate N-sulfonylated aminoalcohols with one or two stereogenic centers were prepared and applied as chiral ligands in the titanium(IV)-catalyzed asymmetric addition of diethylzinc to aldehydes, affording excellent enantioselectivities of up to 98% e.e.
Dual Stereoselectivity in the Dialkylzinc Reaction Using (−)-β-Pinene Derived Amino Alcohol Chiral Auxiliaries
作者:Caitlin M. Binder、April Bautista、Marek Zaidlewicz、Marek P. Krzemiński、Allen Oliver、Bakthan Singaram
DOI:10.1021/jo802371z
日期:2009.3.20
morpholino group through a simple substitution reaction. 3-MAP was characterized by X-ray crystallography, which displayed the rigidity of the pinane framework. Amino alcohol 2-MAP was prepared from its trans isomer 2, which in turn was synthesized via hydroboration/oxidation of the morpholine enamine of (+)-nopinone. Two-dimensional NMR was used to characterize amino alcohol 2-MAP, and NOE was used to confirm
The first catalytic enantioselective 1,2-reduction of enones with 0.45 mol equiv potassium borohydride solution catalyzed by a chiralN,N′-dioxide–Sc(III) complex catalyst was accomplished under mild reaction conditions. A number of optically active allylic alcohols were obtained in good to excellent enantioselectivities (up to 95% ee) with nearly quantitative yields.
Synthetic approach toward cis-disubstituted γ- and δ-lactones through enantioselective dialkylzinc addition to aldehydes: application to the synthesis of optically active flavors and fragrances
to optically active cis-4,5-disubstituted γ- and δ-lactones by catalytic enantioselective addition of dialkyzincs to cinnamic aldehydes and RCM ring closure has been reported. The synthetic importance of the enantioselective dialkylzinc alkylation of aldehydes has been thus widened. Such an approach has then been employed for the enantioselective synthesis of naturally occurring γ-lactone flavors like