39628-06-3Relevant academic research and scientific papers
Sulfuryl Fluoride Mediated Synthesis of Amides and Amidines from Ketoximes via Beckmann Rearrangement
Gurjar, Jitendra,Fokin, Valery V.
supporting information, p. 10402 - 10405 (2020/07/25)
A metal-free and redox-neutral method for Beckmann rearrangement employing inexpensive and readily available SO2F2 gas is described. The reported transformation proceeds at ambient temperature and is compatible with a wide range of sterically and electronically diverse aromatic, heteroaromatic, aliphatic and lignin-like oximes providing amides in good to excellent yields. The reaction proceeds through the formation of an imidoyl fluoride intermediate that can also be used for the synthesis of amidines.
Beckmann rearrangement of OTDP salts of oximes of aromatic ketones and synthetic applications
Thiebaut, Sylvie,Gerardin-Charbonnier, Christine,Selve, Claude
, p. 1329 - 1340 (2007/10/03)
Reaction between tris(dimethylamino)-phosphine, carbon tetrachloride and oximes of ketones leads to the corresponding Oximoxy-Tris-(Dimethylamino)- Phosphonium salts (OTDP salts), which are isolated in the form of hexafluorophosphates. These salts are solid and stable except if they are completely dehydrated. Their solutions, in non polar solvents like CHCl3 , give Beckmann rearrangement at room temperature. The kinetics and mechanism have been studied by NMR. We have defined the conditions of trapping of the cationic intermediates formed in the rearrangement, leading to an effective synthesis of amidines and an access to a glycoside structure using the hemiacetalic hydroxyl group of sugar as nucleophile.
Amidines. Part 30. Influence of Substitution at Amino Nitrogen Atom on pKa Values of N2-Phenylacetamidines and N2-Phenylamidines
Oszczapowicz, Janusz,Krwczyk, Waldemar,Lyzwinski, Przemyslaw
, p. 311 - 314 (2007/10/02)
A series of N2-phenylacetamidines and N2-phenylformamidines (22 compounds) containing variable substituents at amino nitrogen atom have been synthesized, and their pKa values in 95.6percent ethanol (azeotrope) measured.The pKa values obtained for N1-methyl-N1,N2-diphenylacetamidines were correlated with Hammett type constants.Applicability of various ? values is discussed and it is shown that for substituents on the phenyl ring at amino nitrogen atom ?0 values should be used.It is also shown that the pKa values of amidines correlate well with the pKa values of corresponding secondary amines, and that this correlation can serve the prediction of the pKa of amidine. Comparison of the correlations obtained for studied acetamidines and formamidines indicates that sensitivity of the amidino group to substitution at the amino nitrogen atom depends to a certain degree on the substituent at the functional carbon atom.
