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Treatment of polyamides in an ionic liquid at 300°C resulted in the efficient depolymerization of polyamides to give corresponding monomeric lactam in good yields. The recovered monomer was collected by direct distillation of the reaction mixture. PP13 TFSI furnished the best results for the depolymerization. The ionic liquid could be recycled five times in the present reaction.Development of an effective method for treating waste plastics is one of the important problems in recent environmental issues. Among several treatments developed thus far, the ideal one is undoubtedly chemical recycling, in which waste plastics are converted into corresponding monomers suitable for repolymerization reactions that reform recycled plastic. 1 To accomplish optimal recycling, an easy and efficient method to depolymerize polymers into corresponding monomers must be developed. Depolymerization methods developed thus far are usually performed under hightemperature conditions, and therefore, high-boiling-point solvents or high-pressure apparatus is necessary. For these purposes, supercritical water 2 or other solvent systems 3 frequently have been employed, and pyrolysis of polymers has been used in some cases. 4 These methods have sometimes taken advantage of depolymerization; however, due to the high temperature of the reaction, special care is required to prevent the possibility of fire. In addition, special apparatus that tolerates the high-pressure conditions is essential to perform the reaction. Recently, ionic liquids have been of interest in many fields of chemistry because of their unique properties such as solubility, nonvolatility, highreactivity, low-flammability, etc. 5 Nonvolatility and stability at high temperature make the ionic liquids suitable for this purpose. Moreover, the possibility of recycling is important for achieving a zero-emission recycling system. To the best of our knowledge, thus far, there have been no practical reports on such use of ionic liquids. 6 In this paper, we discuss

Electrolysis of aqueous Mn 2þ ions at an anodic potential of þ1.0 V (vs Ag/AgCl) in the presence of cationic surfactants led to the formation of multilayered manganese oxides intercalated with the surfactant molecules. Their interlayer spacings are much larger than that (∼0.7 nm) of conventional birnessite; i.e., 3.1 nm with cetyltrimethyl ammonium (C16) and 2.4 nm with dodecyltrimethyl ammonium (C12). According to XPS analysis, the molar ratio of C16 to MnO 2 was estimated to be 0.74, in which the C16 fraction of 0.42 is associated with Clanions and the other (0.32) interacts with negative charges on the Mn oxide layer. C16 surfactants accommodated between the Mn oxide layers were not ion-exchanged with Na þ ions in solution but extracted with ethanol. Anodic oxidation of the C16-intercalated Mn oxide (C16/MnO 2 ) film took place in an aqueous Na 2 SO 4 solution, accompanied with insertion of SO 4 2anions for charge compensation, and not deintercalation of the surfactants. As a result, the layered structure with large interlayer space was maintained at anodic potentials. The C16/MnO 2 film effectively oxidized hydroquinone (HQ) to benzoquinone (BQ), in which the high-valent Mn sites (Mn 4þ ) in the oxide were reduced to Mn 3þ . At open circuit potential, the low-valent Mn species were accumulated, leading to a collapse of the C16-intercalated structure within 250 min; however, applying an anodic potential allowed the structure to remain unchanged, in conjunction with the acceleration of HQ oxidation. This can be attributed to the reoxidation of the Mn 3þ ions resulting from HQ oxidation, keeping the charge in the oxide so that the surfactants are not necessary to be deintercalated. Namely, the MnO 2 layer can act as an electron-transfer mediator for the oxidation of HQ occurring in the large interlayer space. The observed catalytic current was 684 times larger than the current observed on the unmodified electrode.

A novel chiral pyrrolizidine base 5 derived from L-proline promotes the Baylis-Hillman reaction of ethyl and methyl vinyl ketones with electron deficient aromatic aldehydes with moderate levels of enantiomeric excess.

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A novel method for the conversion of vinyl triflates into α-trifluoromethylated ketones in the absence of external trifluoromethyl sources is described. This process accomplishes an efficient migration of the trifluoromethyl group of the triflate to the α-position in the ketone through a radical process. The reaction proceeds by the addition of a trifluoromethyl radical to the vinyl triflate and subsequent fragmentation of the trifluoromethane sulfonyl radical. Based on this reaction, a one-pot two-step procedure for the trifluoromethylation of ketones was developed. The method presented herein also allows the transfer of perfluoroalkyl groups from vinyl perfluoroalkanesulfonates, which are readily accessible from alkynes and perfluoroalkanesulfonic acids.

We describe a simple and efficient procedure for nucleophilic borylation of imines in the absence of a photoredox catalyst. Visible light irradiation of an acetonitrile solution of an imine, an NHC-borane, and diphenyl disulfide (10 mol %) provides various stable α-amino NHC-boranes in good yields. The reaction proceeds via addition of a nucleophilic boryl radical to an imine, followed by hydrogen abstraction from thiophenol, which is generated from NHC-borane and diphenyl disulfide.

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