Cassady et al., Journal of Organic Chemistry, 1958, vol. 23, p. 923,924
作者:Cassady et al.
DOI:——
日期:——
A novel and efficient solvent-free and heterogeneous method for the synthesis of primary, secondary and bis-N-acylsulfonamides using metal hydrogen sulfate catalysts
Some metal hydrogen sulfates were used as acid catalysts in the N-acylation of different sulfonamides using carboxylic acid chlorides and anhydrides as acylating agents under both heterogeneous and solvent-free conditions. Al(HSO4)(3) and Zr(HSO4)(4) were found to have the highest activity and catalyze the reactions efficiently to furnish the primary N-acyl sulfonamides (RCONHSO2R'), secondary N-acylsulfonamides (RCONR '' SO2R') and bis-N-acylsulfonamnides [RCO(SO2R')N-R ''-N(SO2R')COR] in good to high yield. The mild reaction conditions, inexpensive and low toxicity of catalysts and easy work-up procedure make this method attractive. (C) 2009 Elsevier Ltd. All rights reserved.
Sulfamidation of 2-Arylaldehydes and Ketones with Chloramine-T
作者:Thomas Baumann、Michael Bächle、Stefan Bräse
DOI:10.1021/ol061410g
日期:2006.8.1
A series of aliphatic and aromatic carbonyl compounds has been transformed into the corresponding sulfamidated products by means of amine-catalyzed nitrene transfer of chloramine-T. Depending on the residues R, either alpha-sulfamidation in the case of aromatic aldehydes and acetone derivatives or direct sulfamidation at the carbonyl functionality of aliphatic aldehydes has been observed. Applying microwave conditions, good to excellent yields under significantly reduced reaction times could be obtained, thus providing a facile access to alpha, alpha-disubstituted amino acids.