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Although aerobic oxidative acylation of amides with alcohols would be a good complement to classical synthetic methods for imides (e.g., acylation of amides with activated forms of carboxylic acids), to date, there have been no reports on oxidative acylation to produce imides. In this study, we successfully developed, for the first time, an efficient method for the synthesis of imides through aerobic oxidative acylation of amides with alcohols by employing a CuCl/TMEDA/nor-AZADO catalyst system (TMEDA = teramethylethylendiamine; nor-AZADO = 9-azanoradamantane N-oxyl). The proposed acylation proceeds through the following sequential reactions: aerobic oxidation of alcohols to aldehydes, nucleophilic addition of amides to the aldehydes to form hemiamidal intermediates, and aerobic oxidation of the hemiamidal intermediates to give the corresponding imides. This catalytic system utilizes O2 as the terminal oxidant and produces water as the sole by-product. An important point for realizing this efficient acylation system is the utilization of a TMEDA ligand, which, to the best of our knowledge, has not been employed in previously reported Cu/ligand/N-oxyl systems. Based on experimental evidence, we consider that plausible roles of TMEDA involve the promotion of both hemiamidal oxidation and regeneration of an active CuII-OH species from a CuI species. Here promotion of hemiamidal oxidation is particularly important. Employing the proposed system, various types of structurally diverse imides could be synthesized from various combinations of alcohols and amides, and gram-scale acylation was also successful. In addition, the proposed system was further applicable to the synthesis of α-ketocarbonyl compounds (i.e., α-ketoimides, α-ketoamides, and α-ketoesters) from 1,2-diols and nucleophiles (i.e., amides, amines, and alcohols).

The decomposition of the Pd-aryl complex (NBu4) 2[Pd2(μ-Br)2Br2(C 6F5)2] (1) to the reduction product C 6F5H was checked in different solvents and conditions. 1 is not stable in N-alkyl amides (DMF, NMP, DMA), cyclohexanone, and diethers (1,4-dioxane, DME) at high temperatures (above 80 C). Other solvents such as nitriles, THF, water, or toluene are safe, and no significant decomposition occurs. The solvent is the source of hydrogen, and the decomposition mechanisms have been identified by analyzing the reaction products coming from the solvent. β-H elimination involving the methyl group in a N-coordinated amide is the predominant pathway for amides. An O-coordinated diether undergoes β-H elimination and subsequent deprotonation of the resulting oxonium salt to give an enol ether. A palladium enolate from cyclohexanone leads to cyclohexenone, a reaction favored by the presence of a base. Oxygen strongly increases the extent of decomposition, and we propose this occurs by reoxidation of the Pd(0) species formed in the process and regeneration of active Pd(II) complexes.

A fast and efficient one-step approach to the synthesis of dienamides is reported. This concise methodology relies on the use of imides as reactive intermediates and allows for the preferential formation of Z,E-dienamides in good yields.

A fast, flexible, and efficient approach for the stereocontrolled synthesis of enamides has been developed starting from lactams and amides through the use of imides. This new approach provides access to enamide systems not easily or currently accessible through other approaches.

A convenient methodology for the deprotection of N-allylic amide-like moieties was developed. The first examples accounting for the ruthenium-catalyzed deallylation of amides, lactams, imides, pyrazolidones, hydantoins, and oxazolidinones have been achieved by the sequential use of Grubbs carbene (isomerization step) and RuCl3 (oxidation step). A variety of substrates, including enantiopure multifunctional β- and γ-lactams, can be employed.

The photocyclisation of substituted N-phenacyl lactams led to the functionalized highly strained 1-azabicyclo alkanes (n=3,4,5), in good yields.Their easy transformation into monocyclic compounds have been studied.

The uncatalysed autoxidation of aqueous of tertiary aliphatic amineshas been studied in order to obtain information concerning the mechanism of oxidation of Sirotherm resins.Oxidation occurs most rapidly in the free base, and the general correlation of rate with pKa or ionization potential suggests that electron transfer to form an aminium radical cation is rate-determining.The reaction is not initiated by free radical initiators, nor inhibited by radical traps.It is significantly catalysed by strong electron acceptors and by light and is moderately inhibited by the electron donor N-phenylanthranilic acid.Pyrrolidines and hexahydroazepines are oxidized faster than piperidines, and hydroxyl groups on β-carbons increase the rate of oxidation, while those on γ-carbons decrease it.The major products of autoxidation of alkyl pyrrolidines in water were found to be N-oxides.Various pyrrolidinones were isolated in smaller yield.

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