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Abstract: Oxidation of 4-substituted 2,2-bis(trifluoromethyl)thietanes by m-chloroperoxybenzoic acid results in selective formation of the corresponding S-oxides in 65–86% yield. Oxidation of 4-C2H5S-2,2-bis(trifluoromethyl)thietane under mild conditions led to selective formation of 4-C2H5SO2-2,2-bis(trifluoromethyl)thietane, which under more rigorous conditions was selectively converted into trans-4-C2H5SO2-2,2-bis(trifluoromethyl)thietane-1-S-oxide. Reaction of 4-substituted 2,2-bis(trifluoromethyl)thietanes with activated aluminum powder results in a highly selective ring expansion process, producing the corresponding 5-fluoro-4-(trifluoromethyl)-2,3-dihydro-2-alkoxythiophenes in 58–93% yield. These compounds were also prepared in 61–85% yield using a “one-pot” procedure, starting from sulfur, hexafluoropropene and the corresponding vinyl ether without isolation of any intermediates. Both 2-i-C3H7O- and 2-t-C4H9O- 5-fluoro-4-(trifluoromethyl)-2,3-dihydrothiophenes were converted into 2-fluoro-3-trifluormethylthiophene by reaction with P2O5. [Copyright &y& Elsevier]

Schicksalswende: Unter oxidativen Bedingungen und der Verwendung von Iodosobenzol erlebt ein kürzlich beschriebenes Zwitterion eine „Wendung des Schicksals“. Die oxidative Cyclisierung einer Reihe von Fluoralkoxy ‐ funktionalisierten Imidazolium ‐ Verbindungen führt dabei zur Bildung von anellierten Imidazolonketalen. [ABSTRACT FROM AUTHOR]

The synthesis of bis[(3a,4,5,6,6a-η)-1,3,4,5,6-pentamethylcyclopenta[d]imidazo-2-thionoyl]iron(II) is reported. Structural determination of the unusual hetero-substituted metallocene by X-ray crystallographic analysis is described. Preliminary electrochemical studies reveal that oxidation and reduction potentials for the subject ferrocene lie midway between those of ferrocene and decamethylferrocene. [ABSTRACT FROM AUTHOR]

Stable urea ketals have remained elusive because of their inherent instability and reactivity. In their Communication on page 10871 ff., A. J. Arduengo III, J. W. Runyon et al. describe the oxidation of a series of imidazolium alkoxides to produce isolable imidazolone spiroketals. The spiral nature of this novel fused‐ring system is reminiscent of the spiral staircases in the Shelby Hall Chemistry Building where it was created. [ABSTRACT FROM AUTHOR]

Mild oxidation of zwitterionic azolium alkoxides (I) and (III) under anhydrous conditions leads to new stable spirocyclic ketals (II) and (IV). [ABSTRACT FROM AUTHOR]