Toshiro Chiba

A facile synthesis of ring-fused alkylidenecyclopropanes by olefination reaction of bicyclo(n.1.0)alkanone N,O-hemiacetals with Wittig reagents

Abstract Ring-fused alkylidenecyclopropanes, bicyclo[ n .1.0]alkylidene derivatives, were readily synthesized by olefination reaction of bicyclo[ n .1.0]alkanone N,O -hemiacetals with Wittig reagents in good yields.

Stereoselective preparation of 7-exo-amino-7-endo-substituted bicyclo[4.1.0]heptanes

Abstract Bicyclo[4.1.0]heptan-7-one N,O-hemiacetals undergo substitution reaction with Wittig reagents (Ph3PCHR3) to give stereoselectively the corresponding 7-exo-amino-7-endo-substituted bicyclo[4.1.0]heptanes in good yields.

Electro-Oxidation of Enamines Using Iodide Ion as a Mediator

A series of pyrrolidinoenamines of an alicyclic ketone (1) was subjected to the indirect electrooxidation in NaCN-MeOH using iodide ion as a mediator. It was found that the electrolysis products were dependent on the ring size of the ketone component. For example, the cyclohexanone and cycloheptanone enamines exclusively provided a ring fused cyclopropane aminonitrile (2),whereas the cyclooctanone enamine yielded only the corresponding β-cyanoenamine (4).

Electrochemical Formation of Favorskii Rearrangement Type Intermediates and Their Reactivities

The indirect electrooxidation of enamines of alicyclic ketones (1) in NaOMe-MeOH using iodide ion as a mediator provided ring fused cyclopropane aminoethers (2). The resulting products were then subjected to acid-catalyzed hydrolysis, alcoholysis, the reductive elimination of the methoxy group with LiAlH4, and the replacement of the methoxy group by a cyano group with Me3SiCN in the presence of a Lewis acid.