Practical copper(i)-catalysed amidation of aldehydes
作者:Joyce Wei Wei Chang、Thi My Uyen Ton、Stefani Tania、Paul C. Taylor、Philip Wai Hong Chan
DOI:10.1039/b918588g
日期:——
The direct synthesis of amides by insertion into the C-H bond of aldehydes is shown to be a practical procedure through application of cheap, readily available catalysts generated in situ from copper(i) halides and pyridine.
Iron(II)-Catalyzed Amidation of Aldehydes with Iminoiodinanes at Room Temperature and under Microwave-Assisted Conditions
作者:Thi My Uyen Ton、Ciputra Tejo、Stefani Tania、Joyce Wei Wei Chang、Philip Wai Hong Chan
DOI:10.1021/jo200284a
日期:2011.6.17
A method for the amidation of aldehydes with PhI=NTs/PhI=NNs as the nitrogen source and an inexpensive iron(II) chloride + pyridine as the in situ formed precatalyst under mild conditions at room temperature or microwave assisted conditions is described. The reaction was operationally straightforward and accomplished in moderate to excellent product yields (20-99%) and with complete chemoselectivity with the new C-N bond forming only at the formylic C-H bond in substrates containing other reactive functional groups. By utilizing microwave irradiation, comparable product yields and short reaction times of 1 h could be accomplished. The mechanism is suggested to involve insertion of a putative iron-nitrene/imido group to the formylic C H bond of the substrate via a H-atom abstraction/radical rebound pathway mediated by the precatalyst [Fe(py)(4)Cl-2] generated in situ from reaction of FeCl2 with pyridine.
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.