A highly regioselective reaction of<i>N</i>-fluoropyridinium salts with stabilized sulfur, oxygen, and nitrogen nucleophiles: A convenient route to 2-substituted pyridines
作者:Alexander S. Kiselyov、Lucjan Strekowski
DOI:10.1002/jhet.5570300530
日期:1993.10
2-Substitutedpyridines are efficiently obtained by the reactions of N-fluoropyridinium tetrafluoroborate or triflate with anions derived from benzenethiols, phenols, azoles, cyanamide, and with azide anion. The results are consistent with a nucleophile addition at the position 2 of the N-fluoropyridinium cation as the major reaction pathway.
provide efficient synthetic access to heteroaryl sulfones in two-steps using a simple palladium–1,1′-bis[(diphenyl)phosphanyl]ferrocene catalyst to form in high yields variously functionalized heteroaromatic thioethers. Pyridinyl-containing substrates can be subsequently selectively oxidized into sulfones and NH-sulfoximines by using very mild oxidation conditions with a high functional group tolerance