Alkylamides oxidation

Mechanisms of aliphatic PA photooxidation under light action in the conditions of amide group absorption [4] where studied. These reactions way flow under the action of short-wave light which boundary at the Earth s surface is 290 nm. The main result of investigations was discovery of the role of radical - CONHCHCH - (Ri ), being the precursor of all basic products of alkylamide oxidation, for example, RC O and Pi, formed at primary photochemical process of photodissociation of amide bond according to the reaction ... 

Amino-3-azidocarbonylfuroxan 143 can be transformed to the /V-alkylamide derivatives 144 of 4-amino-3-furoxancarboxylic acids and their oxidation products 145 (Scheme 36) <2003FES677>. 

Die Oxidation der Schwefelsaure-bis-[alkylamide] kann auch elektrochemisch erfolgen4. Z.B. wird Dicyclohexyl-diazen in 90% Ausbeute bei einer Stromausbeute von 65-75% erhalten. 

As indicated above (Ohme and Schmitz [38a, p. 339]) primary amines converted into the alkylamides of sulfuric acid can be oxidized with sodium hypochlorite to azo compounds. The reaction appears to proceed by way of an intermediate hydrazine, which is ultimately oxidized [38a], The reaction is suitable for the formation of symmetrically substituted azoalkanes. Highly branched primary aliphatic amines have been oxidized with sodium hypochlorite in an aqueous dioxane medium [77],... 

The first tantalum nitrene was obtained in 1959 by thermolysis of [Ta(NEt2)]5-288 This class of compounds is presently accessible by several routes, including hydrogen abstraction from the mono- or di-alkylamides, reaction of metallacarbenes with organic imines, oxidation of low valent species by organic azides, or reductive coupling of nitriles (Table 13). The tantalum derivatives are usually stabler than those of niobium. 

Three of the main active components of Echinacea, cichoric acid, polysaccharides, and alkylamides, were separated and tested at various doses in rats for phagocytic activity in alveolar macrophages and splenocytes. The alveolar macrophages from the group of rats treated with the alkylamides were the only cells to show any significant increases in phagocytic activity, phagocytic index, TNF-cx, and nitric oxide. None of the components tested had any activity on splenocytes (7). 

F. Minisci, C. Punta, F. Recupero, F. Fontana, G. F. Pedulli, Aerobic oxidation of N-alkylamides catalysed by N-hydroxyphatalimide imder mild condiditons. Polar and enthaplic effects, J. Org. Chim. 67 (2002) 2671. 

Other derivatives of p-quinones, such as anthraquinone, mono- and di-sodium sulphonates are photosensitizers of the oxidation of isopropanol [Refs. 84, 105, 106, 158, 662, 663]. Lock and Sagar [377] have suggested that a similar mechanism may occur in the photosensitized oxidation of JV-alkylamides which they studied as a model system simulating the photo-sensitized degradation of polyamides. They suggest that the AT-alkyl radical initially produced may add molecular oxygen to give peroxy radicals which are the precursors of the observed oxidation reaction. 

The kind of complexity that can arise in these systems is well illustrated by the study of the oxidation of A-alkylamides [68,69], Double reactions occurring in the presence of metal ion catalysts are laid out in Scheme 1, the relative importance of each reaction depending on reaction conditions and on electron-directing and steric effects in the molecule. Overall kinetics are given for different reactions [68,69], but the complexity is such that detailed analysis is difficult or impossible. 

Of the 33 papers presented at the symposium 32 are included in this volume. They are of two general types. One type discusses inorganic compounds exhibiting a specific property, most frequently electrical or photochemical. The second type reviews recent developments in the synthetic chemistry of a class of inorganic compounds— most often transition metal or lanthanide complexes— which are of potential interest to persons looking for new systems with unusual properties. Classes of compounds covered by this second type include metal alkyls, metal alk-oxides, metal alkylamides, metal chelates, and metal clusters as well as metal complexes with polyboranes, polyphosphines, macrocyclic derivatives, di- and triketones, and polypyrazolylborates as ligands. 

Reaction with cyclic epoxides. The reaction of epoxides of medium-size rings with base (lithium di- -alkylamides) has been extensively studied by Cope and by Crandall (1, 610 611 2, 247). Two products are usually obtained an allylic alcohol formed by -elimination and a bicyclic alcohol derived from a carbene intermediate formed by a-elimination. Boeckman has now found that the ciirbcnc pathway is highly favored if n-butyllithium (3 equiv.) is used as base and if (he reaction is conducted at low temperatures, —78 to 25° in the case of cis-eyelooctene oxide (1) and m-cyclodecene oxide. The oxide of cyclododecene,... 

Garcia et al. [77,78] reported an electron transfer percolation threshold in highly resistive oil-continuous microemulsions. The Faradaic electron transfer is modulated by the amount of cosurfactant present in AOT-toluene-water microemulsions. Below a certain threshold concentration of the cosurfactant, the electron transfer between electroactive solutes in the water droplets and ultramicroelectrode is retarded or blocked. Electron transfer becomes facilitated, and a sharp increase in Faradaic current is observed above the threshold concentration. This effect was demonstrated for ruthenium hexamine reduction [77,78], ferrocyanide oxidation [77,78], acrylamide oxidation [77], and allQ lamide oxidation [77,79] with acrylamide, alkylamides, and acetonitrile as cosurfactants in AOT microemulsions. NMR results [80] suggest that there is an interfacial packing transition of the surfactant (AOT) at about the same cosurfactant concentration as the threshold transition observed electrochemically. 

In 2011, Hayashi and coworkers [14] reported an iron-catalyzed oxidative coupling of alkylamides 20 and arenes 21 to give benzylamides 25. This domino process... 

Similar threshold phenomena have been reported for the reduction of persulfate in reverse microemulsion polymerization of acrylamide [12,13], for ferrocyanide oxidation in similar microemulsions utilizing acetonitrile as cosurfactant [29], and for the autocatalytic oxidation of acrylamide and a variety of primary alkylamides where the respective amides served as cosurfactant [31]. 

Fig. 3 Square-wave voltammograms (net currents, 24 °C, at 10/rm diameter platinum ultramicroelectrode) for irreversible oxidation of homologous primary alkylamides above threshold in reverse water-AOT-toluene microemulsions. Microemulsions were formulated with 1.77 g AOT, 7.04 g toluene, 0.785 g water, and varying amounts of amide, = 8.4,7.2,7.3, and 7.9% (w/w) for cosurfactants acetamide, propionamide, butyramide, and valeramide, respectively...

It should also be noted that copper-catalyzed Ullmann-type coupling of aryl halides with amines yields substituted products [206], and reaction with diphenylamine has been used to form triaryl-amines [207], Triarylamines may also be formed in a variation of the Meyers reaction [47] by displacement by lithium amides of fluoro- or methoxy-substituents activated by an ort/io-ester function [208], The oxidation of a-adducts is discussed in Chapter 11, but it should also be mentioned that aminated products may also be produced by the oxidation of adducts formed by the addition of amide or alkylamide ions at ring carbon atoms carrying hydrogen [209]. 

The mechanism of photo-oxidative degradation of polyamides has also been investigated using low molecular weight compounds such as JV-hexyl-hexanamide 1,6-hexamethylenebis(hexanamide) iV,JV -bis(hexyl)adipamide N-alkylamides and N-acylamides [587, 1221, 1348, 1683, 1880, 1959]. 

The products from reaction of cyclohexene oxide (149) with a variety of lithium alkylamides have been investigated. Major pathways are considered relevant and these involve rearrangement to allylic alcohol or ketone or direct nucleophilic substitution. With lithium monoalkylamides the reaction product is essentially partitioned between cyclohex-2-enol (150) and amino-adduct... 

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