Katsuaki Miyaji

A highly efficient synthesis of optically pure γ-iodo allylic alcohols and their conversion into various optically active allylic alcohols

Abstract Kinetic resolution of γ-iodo allylic alcohols 1 by the Sharpless asymmetric epoxidation reaction proceeds with very large rate differences for the two enantiomers, thus providing a highly efficient method for preparation of optically pure 1 . The alcohols 1 thus prepared can be readily converted into various secondary allylic alcohols through the coupling reaction with nucleophiles.

Synthesis of corey lactone via highly stereoselective asymmetric Diels-Alder reaction

Abstract We have succeeded in a highly stereoselective asymmetric Diels-Alder reaction between a chiral acrylate 3a derived from commercially available D-pantolactone 2 and 5-benzyloxymethyl-cyclopentadiene 4 to give the adduct 5a in 94% d.e. and 79% yield for the synthesis of Corey lactone 1 .

Synthetic studies on quassinoids: total synthesis of (±)-amarolide

The total synthesis of (±)-amarolide (1), a quassinoid having 10 chiral centers, was accomplished from the previously reported l2β-hydroxy-picrasan-3-one (4) by 18 step reactions.

A new synthetic route of corey lactone having ω-side chain

Corey lactone having ω-side chain 1a is an important intermediate for syntheses of prostaglandins. Now we have succeeded in developing a new synthetic route of 1a from methylenecyclopentanone having ω-side chain 2a. The new synthetic route has two crucial steps as follows. 1) Hydroxymethyl unit introduction by using organozinc reagent. 2) Oxidation of diol to lactone by using N-oxoammonium salt in combination with sodium bromite.

Synthetic studies on quassinoids: a stereoselective construction of the picrasane skeleton

Abstract 12β-Hydroxypicrasan-3-one, a compound having the correct relative stereochemistry of all the six ring-juncture chiral centers of the picrasane skeleton, was synthesized from a known tricyclic compound, using the orthoester Claisen rearrangement and lead tetraacetate oxidation as key reactions.