E. Katayama

Asymmetric synthesis of optically pure α-methyl-β,γ-unsaturated ketones via triethylaluminum-mediated stereospecific pinacol rearrangement of alkenyl groups

Abstract Optically pure α-methyl-β,γ-unsaturated ketones are synthesized by the Et3Al-mediated pinacol-type rearrangement where alkenyl groups migrate stereospecifically with complete retention of the olefin-geometry.

Enantio- and diastereomerically pure threo-homoallylic alcohols via highly stereoselective reduction of α-methyl-β,γ-unsaturated ketones

Abstract Reduction of α-methyl-β,γ-unsaturated ketones with L-Selectride proceeded with high threo -selectivity to afford threo -β-methyl homoallylic alcohols of high enantio- and diastereomerical purities.

Asymmetric pinacol-type rearrangement of α-hydroxy methanesulfonates promoted by triethylaluminum — preparation of optically pure α-aryl and α-vinyl ketones —

Asymmetric (stereospecific) pinacol-type rearrangement of aryl or vinyl group in α-hydroxy methanesulfonates is promoted by Et3Al in CH2Cl2 at −78°C to afford optically pure α-aryl or α-vinyl ketones.

Reductive pinacol-type rearrangement of chiral α-mesyloxy ketones promoted by organoaluminum compounds

Abstract Reductive pinacol-type rearrangement of chiral α-mesyloxy ketones was effected by organoaluminums (DIBAL in combination with Et 3 Al or Et 2 AlCl) leading to enantiomerically pure 2-aryl- or 2-alkenyl-1-propanols.

Stereoselective synthesis of C(1)–C(9) and C(11)–C(17)fragments of protomycinolide iv based on asymmetric pinacol-typerearrangement

Abstract Two chiral intermediates, C(1)–C(9) and C(11)–C(17) portionsof protomycinolide IV, were synthesized both from (S)-ethyl lactatevia asymmetric pinacol-type rearrangement followed bydiastereoselective reactions on α-methyl-β,γ-unsaturatedcarbonyl compounds.

Highly stereoselective approach to chiral building block possessing three contiguous asymmetric centers. Preparation of four possible diastereomers of β,β′-dimethyl-bis-homoallylic alcohol derivative

Abstract All four diastereomere of chiral alcohol 2 with three contiguous chiral centers were stereoselectively prepared via diastereoselective addition of nucleophiles (crotyl metal or H-) to α-methyl-β,γ-unsaturated carbonyl compounds 1 .