Yukio Hanyu

A new strategy to sulfur heterocycles: Reactions of an allene episulfide with electrophiles

Abstract A variety of sulfur-containing five- and six-membered cyclic compounds was obtained by the acid-catalyzed and thermal reactions of an allene episulfide with various electrophiles.

Synthesis of diisopropylidenethiirane (thiiranoradialene) and its reactions

Abstract The first stable 2,3-methylenethiirane, 2,3-diisopropylidene-thiirane 6 , was prepared by pyrolysis of lithium salt of tosylhydrazone of 2, 2-dimethyl-4-isopropylidene-3-thietanone. The desulfurization of 6 by phosphines and carbenes gave 2,5-dimethyl-2,3,4-hexatriene 15 . Photosensitized oxygenation of 6 gave acetone via (2+2) cycloaddition of a double bond with singlet oxygen. MCPBA oxidation of 6 afforded the desired corresponding sulfoxide 16 quantitatively.

Formation of dithia[6] radialenes by boron trifluoride-catalyzed reaction of thiiranoradialenë

Abstract A boron trifluoride-catalyzed reaction of thiiranoradialene 3 afforded dimerization products including two novel dithia[6]radialenes, whose structures were determined by spectroscopies and X-ray crystal analyses.

Synthesis of a novel fused thiirene sulfoxide with endoperoxide and its diels-alder adduct

Abstract Photooxidation of thiiranoradialene sulfoxide afforded a new thiirene sulfoxide fused with an endoperoxide ring, which gave the [2+4]cycloadduct with furan.