98-87-3Relevant articles and documents
Lee,Cubberly
, p. 1061 (1969)
Carbon Atom Insertion into Pyrroles and Indoles Promoted by Chlorodiazirines
Dherange, Balu D.,Kelly, Patrick Q.,Levin, Mark D.,Liles, Jordan P.,Sigman, Matthew S.
supporting information, p. 11337 - 11344 (2021/08/16)
Herein, we report a reaction that selectively generates 3-arylpyridine and quinoline motifs by inserting aryl carbynyl cation equivalents into pyrrole and indole cores, respectively. By employing α-chlorodiazirines as thermal precursors to the corresponding chlorocarbenes, the traditional haloform-based protocol central to the parent Ciamician-Dennstedt rearrangement can be modified to directly afford 3-(hetero)arylpyridines and quinolines. Chlorodiazirines are conveniently prepared in a single step by oxidation of commercially available amidinium salts. Selectivity as a function of pyrrole substitution pattern was examined, and a predictive model based on steric effects is put forward, with DFT calculations supporting a selectivity-determining cyclopropanation step. Computations surprisingly indicate that the stereochemistry of cyclopropanation is of little consequence to the subsequent electrocyclic ring opening that forges the pyridine core, due to a compensatory homoaromatic stabilization that counterbalances orbital-controlled torquoselectivity effects. The utility of this skeletal transform is further demonstrated through the preparation of quinolinophanes and the skeletal editing of pharmaceutically relevant pyrroles.
Electrochemical properties and catalytic reactivity of cobalt complexes with redox-active meso -substituted porphycene ligands
Koide, Taro,Zhou, Zihan,Xu, Ning,Yano, Yoshio,Ono, Toshikazu,Luo, Zhongli,Shimakoshi, Hisashi,Hisaeda, Yoshio
, p. 90 - 97 (2019/08/08)
The cobalt complexes of meso-aryl substituted porphycenes were synthesized and characterized. The reduction potentials of the complexes were shifted to the positive side depending on the strength of the electron-withdrawing properties of the meso-substituents, while the optical properties, such as the absorption spectra of these complexes, were similar. This suggests that the energy levels of the molecular orbitals of the complexes were changed by the meso-substituents while the gaps of the orbitals were not significantly changed. The one-electron reduction of the complex did not afford the Co(I) species, but the ligand-reduced radical anion, which was characterized by electrospectrochemistry. The generated ligand-reduced species reacted with alkyl halides to form the Co(III)-alkyl complex. As a result, the reduction potential of the electrolytic reaction could be directly controlled by the substituents of the porphycene. The catalytic reaction with trichloromethylbenzene was also performed and it was found that the ratio of the obtained products was changed by the reduction potentials of the catalyst, i.e. the cobalt porphycenes.
Synthesis method of benzyl dichloride
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Paragraph 0013-0024, (2019/05/02)
The invention discloses a synthesis method of benzyl dichloride. The method comprises the steps that a catalyst, an inhibitor and 300 g of methylbenzene are added to a four-neck flask; chlorine is added to the four-neck flask to perform chlorination stage treatment, a chlorinated solution A is made after the chlorination stage treatment is completed; finally distillation stage treatment is conducted on the chlorinated solution A at negative pressure, and the benzyl dichloride is obtained after the stage treatment is completed. A methylbenzene catalytic chlorination method is adopted, one or more of dibenzoyl peroxide, azobisisobutyronitrile and acetamide is taken as the catalyst, aliphatic amine or the derivative thereof is taken as the inhibitor, and the synthesis technology has the advantages of less side reaction, low cost, low energy consumption and simple operation.
