2234-16-4Relevant articles and documents
Promoting charge separation in donor-acceptor conjugated microporous polymers: Via cyanation for the photocatalytic reductive dehalogenation of chlorides
Deng, Jiyong,Fang, Zhengjun,Lan, Donghui,Liao, Yunfeng,Liu, Qingquan,Zhang, Weijie,Zhou, Xiang
, p. 7151 - 7159 (2021/11/17)
Conjugated microporous polymers (CMPs) have emerged as promising heterogeneous photocatalysts for organic transformations owing to their structural designability and functional versatility. However, limited by the insufficient separation of the photo-generated excitons, their photocatalytic efficiency falls far short of expectations. Herein, we demonstrate a cyanation strategy to promote charge carrier separation in CMPs by selectively incorporating carbazole and cyano groups as electron-donating and electron-withdrawing units, respectively. The resulting CMPs feature π-extended donor (D)-acceptor (A) conjugation structures endowing them with distinct semiconducting properties, in which the efficient charge separation and transfer and wide visible-light absorption are facilitated. Compared to the cyano-free counterpart, the cyano-functionalized CMPs showed superior photocatalytic efficiency as exemplified by photocatalytic reductive dehalogenation of chlorides. More prominently, full recyclability of the designed CMPs as well as catalytic activity for at least ten runs without the loss of catalytic performance in photocatalytic reductive dehalogenation of chlorides demonstrated their robustness and sustainability. This journal is
Oxidative Cleavage of Alkenes by O2with a Non-Heme Manganese Catalyst
Bennett, Elliot L.,Brookfield, Adam,Guan, Renpeng,Huang, Zhiliang,Mcinnes, Eric J. L.,Robertson, Craig M.,Shanmugam, Muralidharan,Xiao, Jianliang
supporting information, p. 10005 - 10013 (2021/07/19)
The oxidative cleavage of C═C double bonds with molecular oxygen to produce carbonyl compounds is an important transformation in chemical and pharmaceutical synthesis. In nature, enzymes containing the first-row transition metals, particularly heme and non-heme iron-dependent enzymes, readily activate O2 and oxidatively cleave C═C bonds with exquisite precision under ambient conditions. The reaction remains challenging for synthetic chemists, however. There are only a small number of known synthetic metal catalysts that allow for the oxidative cleavage of alkenes at an atmospheric pressure of O2, with very few known to catalyze the cleavage of nonactivated alkenes. In this work, we describe a light-driven, Mn-catalyzed protocol for the selective oxidation of alkenes to carbonyls under 1 atm of O2. For the first time, aromatic as well as various nonactivated aliphatic alkenes could be oxidized to afford ketones and aldehydes under clean, mild conditions with a first row, biorelevant metal catalyst. Moreover, the protocol shows a very good functional group tolerance. Mechanistic investigation suggests that Mn-oxo species, including an asymmetric, mixed-valent bis(μ-oxo)-Mn(III,IV) complex, are involved in the oxidation, and the solvent methanol participates in O2 activation that leads to the formation of the oxo species.
Synthesis method of 2, 4-dichloroacetophenone
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Paragraph 0011-0014, (2020/05/30)
The invention discloses a synthesis method of 2, 4-dichloroacetophenone. The method comprises the following steps: carrying out electrophilic substitution reaction on m-dichlorobenzene and acetyl chloride in an ionic liquid (Bmin)Cl-FeCl3 medium to synthesize the 2, 4-dichloroacetophenone; adding m-dichlorobenzene and acetyl chloride into the (Bmin)Cl-FeCl3 ionic liquid according to a molar ratioof 1:(1.1-1.2), carrying out a stirring reaction for 4h at a temperature of 40-60 DEG C, extracting 2, 4-dichloroacetophenone with cyclohexane, and carrying out reduced pressure distillation to removethe solvent so as to obtain 2, 4-dichloroacetophenone. The weight ratio of the feeding amount of the ionic liquid (Bmim)Cl-FeCl3 to the total feeding amount of m-dichlorobenzene and acetyl chloride is 1:(1-0.8). The method has the advantages that the use of anhydrous aluminum chloride is avoided, the conversion rate of raw materials is improved, byproducts are reduced, and green and environment-friendly production is realized.