Elemental sulfur mediated cyclization via redox strategy: Synthesis of benzothiazoles from o -chloronitrobenzenes and benzyl chlorides
作者:Xin Wang、Dazhuang Miao、Xiaotong Li、Renhe Hu、Zhao Yang、Ren Gu、Shiqing Han
DOI:10.1016/j.tet.2017.07.013
日期:2017.8
A novel metal-free synthesis of 2-substituted benzothiazoles from easily available o-chloronitrobenzenes and benzyl chlorides using elementalsulfur as traceless oxidizing agent has been developed. The protocol provides a simple, efficient, and atom-economic way to access to benzothiazoles in moderate to excellent yields. And the approach exhibited good functional group tolerance.
Aerobic oxidative synthesis of quinazolinones and benzothiazoles in the presence of laccase/DDQ as a bioinspired cooperative catalytic system under mild conditions
study applied laccase/DDQ as a bioinspired cooperative catalyticsystem for the synthesis of quinazolinones (80–95% yield) and benzothiazoles (65–98% yield) using air or O2 as ideal oxidants in aqueous media at ambient temperature. The aerobicoxidative cyclization reactions occur in two steps: (i) chemical cyclization; (ii) chemoenzymatic oxidation. These methods are more environment-friendly, efficient
目前的研究将漆酶/DDQ 作为一种受生物启发的协同催化系统,在环境温度下使用空气或 O 2作为水介质中的理想氧化剂合成喹唑啉酮(80-95% 产率)和苯并噻唑(65-98% 产率)。好氧氧化环化反应分两个步骤进行: (i) 化学环化;(ii) 化学酶氧化。由于使用O 2作为氧化剂,漆酶作为生态友好的生物催化剂,水性介质作为溶剂,并且不含任何有毒的过渡金属和卤化物,这些方法比其他报道的方法更环保、高效、简单和实用。催化剂。因此,这些方法可以应用于制药和其他敏感的合成过程。
Photoinduced Copper-Catalyzed C−H Arylation at Room Temperature
作者:Fanzhi Yang、Julian Koeller、Lutz Ackermann
DOI:10.1002/anie.201512027
日期:2016.4.4
Room‐temperature azole C−H arylations were accomplished with inexpensive copper(I) compounds by means of photoinduced catalysis. The expedient copper catalysis set the stage for site‐selective C−H arylations of non‐aromatic oxazolines under mild reaction conditions, and provides step‐economical access to the alkaloid natural products balsoxin and texamine.
the synthesis of quinazolinones, quinoxalinones, benzooxazinones, and benzothiazoles from the reactions of α-keto acids with 2-aminobenzamides, benzene-1,2-diamines, 2-aminophenols, and 2-aminobenzenethiols, respectively, is described. The reactions were conducted under catalyst-free conditions, using water as the sole solvent with no additive required, and successfully applied to the synthesis of sildenafil
Heterogeneouscopper catalysis enabled photoinducedC−Harylations under exceedingly mild conditions at room temperature. The versatile hybridcoppercatalyst provided step‐economical access to arylated heteroarenes, terpenes and alkaloid natural products with various aryl halides. The hybridcoppercatalyst could be reused without significant loss of catalytic efficacy. Detailed studies in terms of