2449-05-0Relevant articles and documents
Synthesis of α-aminocarbonyl compounds via hetero dielsalder reaction
Sakurai, Masayoshi,Kihara, Nobuhiro,Watanabe, Nobuhiro,Ikari, Yoshihiro,Takata, Toshikazu
, p. 144 - 147 (2018/01/01)
A synthetic route to α-aminoketone derivatives via a hetero DielsAlder reaction is described. Diacylhydrazine was oxidized by tert-butyl hypochlorite in the presence of pyridine. After evaporation, the hetero DielsAlder reaction with diene was carried out without isolation of the azodicarbonyl compound. Quantitative hetero DielsAlder reaction was possible with 1 equivalent of diene when Hf(OTf)4 or AgOTf was used as the catalyst. The NN bond of the product was cleaved by SmI2-reduction in the presence of tert-BuOH in THF. Further, ozonolysis of the C=C double bond afforded the α-aminoketone derivative in excellent yield.
Photocatalytic esterification under Mitsunobu reaction conditions mediated by flavin and visible light
M?rz,Chudoba,Kohout,Cibulka
supporting information, p. 1970 - 1975 (2017/03/11)
The usefulness of flavin-based aerial photooxidation in esterification under Mitsunobu reaction conditions was demonstrated, providing aerial dialkyl azodicarboxylate recycling/generation from the corresponding dialkyl hydrazine dicarboxylate. Simultaneously, activation of triphenylphosphine (Ph3P) by photoinduced electron transfer from flavin allows azo-reagent-free esterification. An optimized system with 3-methylriboflavin tetraacetate (10%), oxygen (terminal oxidant), visible light (450 nm), Ph3P, and dialkyl hydrazine dicarboxylate (10%) has been shown to provide efficient and stereoselective coupling of various alcohols and acids to esters with retention of configuration.
Metal-free oxyaminations of alkenes using hydroxamic acids
Schmidt, Valerie A.,Alexanian, Erik J.
, p. 11402 - 11405 (2011/09/16)
A radical-mediated approach to metal-free alkene oxyamination is described. This method capitalizes on the unique reactivity of the amidoxyl radical in alkene additions to furnish a general difunctionalization using simple diisopropyl azodicarboxylate (DIAD) as a radical trap. This protocol capitalizes on the intramolecular nature of the process, providing single regioisomers in all cases. Difunctionalizations of cyclic alkenes provide trans oxyamination products inaccessible using current methods with high levels of stereoselectivity, complementing cis-selective oxyamination processes.
An improved oxidation method for the synthesis of azodicarbonyl compounds
Starr, Jeremy T.,Rai, Gurdev S.,Dang, Hung,McNelis, Brian J.
, p. 3197 - 3200 (2007/10/03)
Five representative hydrazo compounds have been oxidized in high yield using Br2 and pyridine. Yields range from 80% to 93%. For the synthesis of dibenzyl azodicarboxylate, this process produced analytically pure material directly from the reaction mixture.
Oil-soluble bicarbamamide compounds
-
, (2008/06/13)
The oil-soluble azo compounds of this invention are useful as dispersants, corrosion inhibitors and anti-wear agents in lubricating oil and fuel compositions. The predominant oil-soluble azo reaction product may be represented by the following formulas: STR1 wherein R represents an oil-solubilizing, synthetic, polymeric organic radical containing at least 20 carbon atoms, Y is independently selected from the group consisting of --NR2 R3 and --SR4, R2, r3, and R4 are independently selected from hydrogen, alkyl, cycloalkyl, aryl, alkaryl and aralkyl, X is independently selected from oxygen, sulfur and =NR5, with the proviso that when X is =NR5, Y is --NR2 R3, R5 is selected from the group consisting of alkyl, cycloalkyl, aryl and alkaryl, Z represents a polyvalent organic radical having a valence of n and selected from hydrocarbon, oxahydrocarbon, azahydrocarbon and thiahydrocarbon radicals and their oxygenated and halogenated derivatives, E is a monovalent radical selected from alkyl, cycloalkyl, aralkyl, aryl, and alkaryl, and n is an integer from 2 to 5.
