Cuprous Oxide Catalyzed Oxidative CC Bond Cleavage for CN Bond Formation: Synthesis of Cyclic Imides from Ketones and Amines

Abstract

Selective oxidative cleavage of a C-C bond offers a straightforward method to functionalize organic skeletons. Reported herein is the oxidative C-C bond cleavage of ketone for C-N bond formation over a cuprous oxide catalyst with molecular oxygen as the oxidant. A wide range of ketones and amines are converted into cyclic imides with moderate to excellent yields. In-depth studies show that both α-C-H and β-C-H bonds adjacent to the carbonyl groups are indispensable for the C-C bond cleavage. DFT calculations indicate the reaction is initiated with the oxidation of the α-C-H bond. Amines lower the activation energy of the C-C bond cleavage, and thus promote the reaction. New insight into the C-C bond cleavage mechanism is presented.

Ru-Catalyzed Selective C–H Bond Hydroxylation of Cyclic Imides

“…1 H NMR (400 MHz, CDCl 3 ): δ 7.83 (d, J = 7.6 Hz, 1H), 7.75 (dd, J = 0.8, 0.8 Hz, 1H), 7.59–7.56 (m, 1H), 7.52–7.48 (m, 2H), 7.45–7.37 (m, 3H), 2.55 (s, 3H) ppm. The spectral data match those previously reported …”

“…The spectral data match those previously reported. 31 N-Phenyl-4-tert-butylphthalimide (1s). Prepared according to method A starting from 4-tert-butylphthalic anhydride in 93% isolated yield (1.3 g).…”

Hierarchical Mesoporous RuO2/Cu2O Nanoparticle-Catalyzed Oxidative Homo/Hetero Azo-Coupling of Anilines

“…Thus, to meet the urgent demand of sustainable development of this transformation, introduction of a novel nanocatalyst is much desired. Very recently, mixed metal oxide nanostructures have been proven to be the promising green catalytic system in clean chemical synthesis. , Essentially, the synergy between two metal cores improves the red-ox properties at their interfaces which facilitate selective oxidative organic transformations. − Herein, we report the fabrication of a novel nanocrystalline mesoporous hierarchical RuO 2 /Cu 2 O for selective aerobic oxidative homo/hetero azo-coupling of anilines under oxidant/base/additives-free conditions (Scheme b). Initially, the mesoporous hierarchical RuO 2 /Cu 2 O nanoparticles (NPs) were prepared in aqueous medium under microwave irradiation and then analyzed by various analytical techniques (Figure ).…”

Copper(II)-Dioxygen Facilitated Activation of Nitromethane: Nitrogen Donors for the Synthesis of Substituted 2-Hydroxyimino-2-phenylacetonitriles and Phthalimides

“…No phthalic acid could be obtained without the addition of CuSO 4 .5H 2 O and DMAP under dinitrogen atmosphere (Scheme 4C). This result indicates that the oxidation of 1-indanone to phthalic acid could be achieved by the activate oxygen, probably coordinating on the Cu(II) intermediate (Wang et al, 2015). The aromatic ketone species underwent a C-C bond cleavage to form an intermediate species of o-phthalic anhydride during the reaction, and the insertion of nitrogen donor occurred with the species of o-phthalic anhydride (Scheme 6).…”

“…The deprotonation of the second hydrogen atoms of the methylene group of (i) with the transfer of the pair electrons to the C-N bond generates the compound 2a (Scheme 6-(II)). On the other hand, the continuous oxidation of 1indanone (j) in the presence of [Cu II (DMAP) 2 (SO 4 )] and dioxygen generates the intermediate species o-phthalic anhydride (n) (Scheme 6-(III)) (Wang et al, 2015). Meanwhile, the methyl nitrite (f) undergoes a thermal decomposition reaction to generate the species HCHO and HNO (Brower, 1988;Zhu et al, 2013).…”