172288-33-4Relevant academic research and scientific papers
Bond-Weakening Catalysis: Conjugate Aminations Enabled by the Soft Homolysis of Strong N-H Bonds
Tarantino, Kyle T.,Miller, David C.,Callon, Ted A.,Knowles, Robert R.
supporting information, p. 6440 - 6443 (2015/06/08)
The ability of redox-active metal centers to weaken the bonds in associated ligands is well precedented, but has rarely been utilized as a mechanism of substrate activation in catalysis. Here we describe a catalytic bond-weakening protocol for conjugate a
N-methylimidazole-catalyzed synthesis of carbamates from hydroxamic acids via the lossen rearrangement
Yoganathan, Sabesan,Miller, Scott J.
supporting information, p. 602 - 605 (2013/04/11)
An efficient, one-pot, N-methylimidazole (NMI) accelerated synthesis of aromatic and aliphatic carbamates via the Lossen rearrangement is reported. NMI is a catalyst for the conversion of isocyanate intermediates to the carbamates. Moreover, the utility of arylsulfonyl chloride in combination with NMI minimizes the formation of often-observed hydroxamate-isocyanate dimers during the sequence. Under the present conditions, lowering of temperatures is also possible, enabling a mild protocol.
One-pot curtius rearrangement processes from carboxylic acids
Leogane, Olivier,Lebel, Helene
scheme or table, p. 1935 - 1940 (2009/12/29)
An efficient and practical synthesis of amine derivatives from carboxylic acids is described using new one-pot Curtius rearrangement processes. The preparation of carbamate-protected amines and anilines, as well as ureas was achieved in good to excellent yields on a multigram scale. Georg Thieme Verlag Stuttgart.
Curtius rearrangement of aromatic carboxylic acids to access protected anilines and aromatic ureas
Lebel, Helene,Leogane, Olivier
, p. 5717 - 5720 (2007/10/03)
(Diagram presented) The reaction of a chloroformate or di-tert-butyl dicarbonate and sodium azide with an aromatic carboxylic acid produces the corresponding acyl azide, presumably through the formation of an azidoformate. The acyl azide undergoes a Curtius rearrangement to form an isocyanate derivative which is trapped either by an alkoxide or by an amine to form the aromatic carbamate or urea. The reaction conditions are compatible with a variety of functional groups and allow the synthesis of a number of aniline derivatives containing alkyl, halide, nitro, ketone, ether, and thioether substituents.
