DEPROTECTION OF 2-PYRIDYL SULFONYL GROUP FROM PYRIDINE-2-SULFONAMIDES BY MAGNESIUM IN METHANOL
摘要:
Convenient deprotection of various pyridine-2-sulfonamides prepared by sulfonylation of primary and secondary amines with pyridine-2-sulfonylchloride was achieved by magnesium in methanol at 0 degreesC to the corresponding amines in good yield.
PdII-Catalyzed CH Olefination of N-(2-Pyridyl)sulfonyl Anilines and Arylalkylamines
作者:Alfonso García-Rubia、Beatriz Urones、Ramón Gómez Arrayás、Juan C. Carretero
DOI:10.1002/anie.201105611
日期:2011.11.11
N‐(2‐pyridyl)sulfonyl group acts as a removable directing group in the PdII‐catalyzed aryl CH ortho alkenylation of N‐alkyl aniline, benzylamine, and phenethylamine derivatives with electron‐poor alkenes. The products were obtained in high yields (70–90 %) and with complete regiocontrol. The mild reductive N‐sulfonyl removal enables the construction of a variety of nitrogen heterocycles. EWG=electron‐withdrawing
Heterocyclic pentafluorophenyl sulfonate esters are shelf stable alternatives to the often less stable sulfonyl chlorides. They are easily prepared from thiols and react readily with primary and secondary amines to produce sulfonamides in high yields. (c) 2009 Elsevier Ltd. All rights reserved.