32763-28-3Relevant academic research and scientific papers
A Phosphine-Mediated Dearomative Skeletal Rearrangement of Dianiline Squaraine Dyes
Bacher, Emily P.,Koh, Kevin J.,Lepore, Antonio J.,Oliver, Allen G.,Wiest, Olaf,Ashfeld, Brandon L.
supporting information, p. 2853 - 2857 (2021/05/05)
A phosphorus(III)-mediated dearomatization of ortho-substituted dianiline squaraine dyes results in an unusual skeletal rearrangement to provide exotic, highly conjugated benzofuranone and oxindole scaffolds bearing a C3 side chain comprised of a linear conflagration of an enol, a phosphorus ylide, and 2,4-disubstituted aniline. Employing experimental and computational analysis, a mechanistic evaluation revealed a striking dependence on the acidity of the aniline ortho substituent. Notably, the rearrangement adducts underwent rapid and complete reversion to the parent squaraine in the presence of a Br?nsted acid.
Synthesis and NMR-spectral characterization of N,N-dialkyl-3-nitroanilines, N,N-dialkyl-1,3-benzenediamines and their acyl derivatives
Katritzky, Alan R.,Rachwal, Bogumila,Rachwal, Stanislaw
, p. 337 - 345 (2007/10/02)
A recently discovered method for the synthesis of N,N-dialkyl-1,3-benzenediamines with two different alkyl groups is shown to be general.This is demonstrated by the synthesis of N-butyl-N-phenethyl-1,3-benzenediamine by the condensation of 3-nitroaniline with phenylacetaldehyde and benzotriazole, reduction of the adduct with sodium borohydride, acylation of the resulting N-phenethyl-3-nitroaniline with butyryl chloride, catalytic reduction of the nitro group by formic acid in the presence of triethylamine and palladium and finally reduction of the butyramide carbonyl group to the butyl substituent by lithium aluminium hydride.Several other routes were less efficient or failed completely.Classical methods for the synthesis of N,N-diethyl-1,3-benzenediamine were reexamined and improved.The recommended procedure involves alkylation of 3-nitroaniline with diethyl sulfate, trapping of N-ethyl-3-nitroaniline (by-product) by benzoylation, distillation of N,N-diethyl-3-nitro-aniline under reduced pressure and reduction of the nitro group by formic acid catalyzed by palladium.
