18368-65-5Relevant articles and documents
Grignard-Reagent-Promoted Desulfonylation/Intramolecular Coupling for the Synthesis of 2-(1-Fluorovinyl)pyridines
Jiang, Gaoxi,Kang, Lei,Qian, Jinlong,Yang, Huameng,Zhang, Jinlong
supporting information, p. 9118 - 9122 (2020/12/02)
A novel process involving Grignard-reagent-promoted desulfonylation/intramolecular coupling of readily available α-fluoro-α,β-unsaturated-(2-pyridyl)sulfones was realized that provided a series of polysubstituted 2-(1-fluorovinyl)pyridines in good yields. The intrinsic coordination between pyridine and Mg(II) along with the "negative fluorine effect"of the substrates should play the key role for the smooth transformation in the absence of transition-metal catalysts.
Synthesis and characterization of 2-pyridylsulfur pentafluorides
Kanishchev, Oleksandr S.,Dolbier, William R.
supporting information, p. 280 - 284 (2015/04/21)
Current approaches to prepare SF5-substituted heterocycles during the synthesis of targeted heterocyclic compounds require the use of SF5-functionalized aryl or alkyne reagents or SF5Cl as a source of the SF5 functional group. Herein we report that excess oxidative fluorination of 2,2' -dipyridyl disulfide with a KF/Cl2 /MeCN system leads to the formation of thirteen new 2-pyridylsulfur chlorotetrafluorides (2-SF4Cl-pyridines). These molecules are found to undergo further chlorine-fluorine exchange reactions by treatment with silver(I) fluoride enabling ready access to a series of ten new substituted 2-pyridylsulfur pentafluorides (2-SF5-pyridines). This is the first preparatively simple and readily scalable example of the transformation of an existing heterocyclic sulfur functionality to prepare SF5-substituted heterocycles.
Modelling nucleophilic substitution at silicon in solution using hypervalent silicon compounds based on 2-thiopyridones
Bassindale, Alan R.,Parker, David J.,Taylor, Peter G.
, p. 1059 - 1066 (2007/10/03)
Halodimethylsilylmethyl derivatives of 2-thiopyridones have been prepared. The N-CH2 isomer is favoured with the 6-methylthiopyridone. 13C and 29Si chemical shifts have been used to calculate the extent of sulfur-silicon bond formation and the extent of pentacoordination. The results are consistent with the oxygen analogues and reveal that as expected sulfur is a poorer nucleophile than oxygen. The unsubstituted thiopyridone and the 5-trifluoromethyl derivative favour the S-CH2 isomer. Again the mapping of nucleophilic substitution by nitrogen is in line with sulfur and oxygen nucleophiles, but in this series nitrogen is a poorer nucleophile than expected. The results are discussed in terms of steric strain, the preferences for alkylation of the pyridones and the bond strength of coordination to silicon.