194788-16-4Relevant academic research and scientific papers
Carbamate as an accelerating group in intermolecular Pauson-Khand reaction
Asano, Shota,Itto-Nakama, Kaori,Arimoto, Hirokazu
supporting information, (2020/05/05)
The Pauson-Khand reaction (PKR) is a powerful means for the construction of cyclopentenones. However, its applications have been limited to the intramolecular version of this reaction because poor yield and regioselectivity are often the major problems in intermolecular PKR. Here we describe that a carbamate moiety in alkene substrate accelerates this intermolecular PKR. The reaction of N-4-dimethylaminophenyl O-allyl carbamate with alkyne-cobalt complex gave cyclopentenones in high yield (up to 90%) and regioselectivity (>9:1).
Formation of Ketenimines via the Palladium-Catalyzed Decarboxylative π-Allylic Rearrangement of N-Alloc Ynamides
Alexander, Juliana R.,Cook, Matthew J.
supporting information, p. 5822 - 5825 (2017/11/10)
A new approach for the formation of ketenimines via a decarboxylative allylic rearrangement pathway that does not require strong stabilizing or protecting groups has been developed. The products can be readily hydrolyzed into their corresponding secondary amides or reacted with sulfur ylides to perform an additional [2,3]-Wittig process. Mechanistic studies suggest an outer-sphere process in which reductive alkylation is rate-limiting.
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.
Azide monoliths as convenient flow reactors for efficient Curtius rearrangement reactions
Baumann, Marcus,Baxendale, Ian R.,Ley, Steven V.,Nikbin, Nikzad,Smith, Christopher D.
experimental part, p. 1587 - 1593 (2008/10/09)
The preparation and use of an azide-containing monolithic reactor is described for use in a flow chemistry device and in particular for conducting Curtius rearrangement reactions via acid chloride inputs. The Royal Society of Chemistry 2008.
