Chemo- and Diastereoselectivity in the Dimethyldioxirane Oxidation of 2,3-Dihydro-4<i>H</i>-1-benzothiopyran-4-ones and 4<i>H</i>-1-Benzothiopyran-4-ones. Unusual Reactivity of 4<i>H</i>-1-Benzothiopyran-4-one 1-Oxides<sup>1</sup>
the corresponding sulfides. The observed anomaly may be explained in terms of transannular stabilization of the transition structure (TS) for the sulfone formation, promoted through favorable conformational effects in the sulfoxide. Higher sulfoxide/sulfone ratios were found in solvents of greater hydrogen bond donor capacity, which is in accordance with the postulated stabilizing effect.
Facile Synthesis of Tetrazolylchromonoids and Related Compounds
作者:Tamás Patonay、Albert Lévai
DOI:10.1002/ardp.19943270310
日期:——
The reaction between the appropriate nitriles and tributyltin azide (TBTA) provides an easy and efficient method for the synthesis of the title compounds. Treatment of thiocyanate 9b with TBTA affords the alkylthio‐substituted tetrazole 10b.