4285-42-1Relevant articles and documents
Self-Immolative System for Disclosure of Reactive Electrophilic Alkylating Agents: Understanding the Role of the Reporter Group
Chippindale, Ann M.,Gavriel, Alexander G.,Hayes, Wayne,Khurana, Gurjeet S.,Leroux, Flavien,Lewis, Viliyana G.,Russell, Andrew T.,Sambrook, Mark R.
, p. 10263 - 10279 (2021/08/16)
The development of stable, efficient chemoselective self-immolative systems, for use in applications such as sensors, requires the optimization of the reactivity and degradation characteristics of the self-immolative unit. In this paper, we describe the effect that the structure of the reporter group has upon the self-immolative efficacy of a prototype system designed for the disclosure of electrophilic alkylating agents. The amine of the reporter group (a nitroaniline unit) was a constituent part of a carbamate that functioned as the self-immolative unit. The number and position of substituents on the nitroaniline unit were found to play a key role in the rate of self-immolative degradation and release of the reporter group. The position of the nitro substituent (meta- vs para-) and the methyl groups in the ortho-position relative to the carbamate exhibited an influence on the rate of elimination and stability of the self-immolative system. The ortho-methyl substituents imparted a twist on the N-C (aromatic) bond leading to increased resonance of the amine nitrogen's lone pair into the carbonyl moiety and a decrease of the leaving character of the carbamate group; concomitantly, this may also make it a less electron-withdrawing group and lead to less acidification of the eliminated β-hydrogen.
Method for continuously synthesizing buprofezin
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Paragraph 0043-0061, (2020/12/30)
The invention discloses a method for continuously synthesizing buprofezin, and belongs to the technical field of chemical synthesis. The method for continuously synthesizing buprofezin comprises the following steps: S1, continuously acylating N-methylaniline and phosgene in a solvent, and continuously deacidifying to obtain an acyl chloride solution; S2, carrying out continuous chlorination and continuous deacidification on the acyl chloride solution and chlorine under the action of an initiator to obtain a chloride solution; S3, adding buprothiourea, a catalyst and an acid-binding agent intothe chloride solution, carrying out continuous mixing reaction, crystallizing and drying a reaction product to obtain buprofezin of which the content is greater than or equal to 99.0% and the total yield is greater than or equal to 88% based on N-methylaniline. The method for continuously synthesizing buprofezin solves the defects caused by batch production in China, has the advantages of continuous reaction, high automation degree, small equipment size, high operation safety, few side reaction products, high conversion rate and good product quality, can effectively improve the production efficiency and reduce the production cost, and has very good popularization and application values.
Ir-Catalyzed C-H Amidation Using Carbamoyl Azides for the Syntheses of Unsymmetrical Ureas
Yoo, Kwangho,Lee, Jooyeon,Park, Myung Hwan,Kim, Youngjo,Kim, Hyun Jin,Kim, Min
, p. 6233 - 6241 (2020/05/22)
An iridium-catalyzed C-H amidation for the syntheses of unsymmetrical urea was developed using carbamoyl azides (R(R′)N-C(O)-N3) as the nitrogen source. A combination of iridium and silver gave an active catalyst for C-N bond formation. A variety of urea derivatives were synthesized using carbamoyl azides with only dinitrogen byproducts. Finally, the use of the transient directing group strategy with carbamoyl azides extended the substrate scope of the catalytic C-H amidation to yield aldehyde-containing unsymmetrical ureas.
