307001-86-1Relevant articles and documents
A Practical Oxidative Method for the Cleavage of Hydrazide N-N Bonds
Fernandez, Rosario,Ferrete, Ana,Llera, Jose M.,Magriz, Antonio,Martin-Zamora, Eloisa,Diez, Elena,Lassaletta, Jose M.
, p. 737 - 745 (2004)
The selective N-oxidation of the most nucleophilic amino nitrogen atom in hydrazides is central to the development of an unprecedented methodology for the cleavage of their N-N bonds under oxidative conditions. Treatment of a series of hydrazides 1-9 with peracids such as magnesium monoperoxyphtalate hexahydrate (MMPP·6H2O) or meta-chloroperbenzoic acid (m-CPBA) afforded the corresponding amides 10-16 in good-to-excellent yields (80-92%). The extension of the methodology to carbamate-like substrates such as 17 and 18 was also investigated, but in this case the process is synthetically useless in view of the low yields observed of carbamates 19 and 20 (≈ 15%). Experiments carried out with equivalent amounts of oxidant produced nitrones, such as 26, proceeding from the dialkylamino moiety, and 1H NMR experiments indicated that this product is formed by fast conversion of the parent hydrazide, without detection of the expected hydrazide N-oxides. In addition, the over oxidation of 26 into nitronate 25 proceeds through an unknown intermediate. This oxidative N-N bond cleavage by peracids is an alternative method for the deamination of hydrazides, and constitutes the only solution compatible with substrates carrying functionalities sensitive to reducing conditions.
Enantioselective synthesis of 4-unsubstituted 3-alkoxy- and 3-aminoazetidin-2-ones from formaldehyde N,N-dialkylhydrazones
Fernandez, Rosario,Ferrete, Ana,Lassaletta, Jose M.,Llera, Jose M.,Monge, Angeles
, p. 2893 - 2897 (2007/10/03)
Playing two roles at once, chiral amines from L-proline or D-mannitol act as protecting groups and as chiral auxiliaries in the [2+2] cyclo-addition of formaldehyde hydrazones, such as 1, to ketenes. This strategy, based on the stability of the hydrazones
