133587-80-1Relevant academic research and scientific papers
Base-induced cycloreversion of nitrile oxide cycloadducts: Conversion of imines into secondary and tertiary amides and aromatic aldehydes into acids without a conventional oxidising agent
Aitken, R. Alan,Raut, Swati V.
, p. 747 - 751 (2007/10/03)
A series of substituted Δ2-1,2,4-oxadiazolines (4,5-dihydro-1,2,4-oxadiazoles) 12 have been prepared by 1,3-dipolar cycloaddition of nitrile oxides to imines and are found, upon treatment with KOBut, to undergo cycloreversion to give nitriles and amide anions. These can be protonated to give secondary amides or treated in situ with alkyl halides to give tertiary amides in moderate to good overall yield, although the reaction is restricted to examples with an aromatic substituent at the 5-position. The 1,4,2-dioxazoles 15, formed by cycloaddition of benzonitrile oxide to aromatic aldehydes, similarly undergo cycloreversion allowing direct conversion either into substituted benzoic acids or their methyl esters. Copyright 1996 by the Royal Society of Chemistry.
Intramolecular motions in a series of crystalline benzylammonium bromides and dibenzylamines studied by CP/MAS NMR
Riddell, Frank G.,Rogerson, Martin
, p. 493 - 504 (2007/10/03)
A series of 15 compounds including ammonium bromides containing one or two benzyl groups with H, methyl, isopropyl, tert-butyl and tert-amyl substituents and dibenzylamihe with N-isopropyl-, N-tert-butyl- and N-tert-amyl substituents have been synthesised and studied by CP/MAS NMR. The results of dynamic NMR studies on the solids suggest that there is a dramatically wide range of molecular motions occurring in this simple series of compounds: A combination of 2D CPEXSY, dynamic line shape analyses and T1ρ measurements reveals the considerable extent of intramolecular group motions including rotations of methyl, tert-butyl, tert-amyl and phenyl groups. Rates of rotation and activation parameters for these molecular motions are derived where appropriate. In the case of benzyl-tert-butylammonium bromide, where two independent molecules of the compound exist in the asymmetric unit it is shown that the independent processes of tert-butyl rotation in the two molecules have vastly different activation energies that differ by ca. 16 kJ mol-1. The extent of the motions observed suggests that commonly held prejudices about the rigidity of molecules in crystalline solids need revising.
Radical Translocation Reactions across Amides. 1,5-Hydrogen-Transfer Reactions of o-Iodobenzamides and N-(o-Iodobenzyl) Amides
Curran, Dennis P.,Liu, Hohgtao
, p. 1377 - 1394 (2007/10/02)
Radicals derived from N,N-disubstituted o-iodobenzamides undergo rapid 1,5-hydrogen-transfer reactions.The regioselectivity of these reactions is coupled to the rotamer population of the starting iodobenzamide, and the products vary with changing amide substituents.Related 1,5-hydrogen-transfer reactions are observed for N-alkyl-N-(o-iodobenzyl)-benzamides and -acetamides.
