Professor Wang Lei, Huaibei Normal University Research Group: synthesis of trifluoromethyl dihydroisoquinolinone in aqueous phase catalyzed by n-allylbenzamide and cf3so2na under visible light at room temperature

Dihydroisoquinolinone is an important structural unit of some natural products and drug molecules It has important biological activities, such as anti-tumor, anti-inflammatory, anti allergy and estrogen, and its application in cancer diagnosis Therefore, the development of effective synthetic methods to construct these compounds has attracted great attention of organic synthetic chemists However, the synthesis of these compounds is very difficult, especially for trifluoromethyl functionalized dihydroisoquinolinone, which usually requires complex raw materials, and the harsh reaction conditions also limit the practicability of these methods, so it is of great significance to develop a green, efficient and simple synthesis method Recently, Professor Wang Lei and Professor Li Pinhua of Huaibei Normal University developed a green and effective strategy for the preparation of trifluoromethyl dihydroisoquinolone, and the relevant results were published online in green chemistry (DOI: 10.1039 / c9gc00938h) Prof Wang Lei is a second-class professor and doctoral supervisor of Huaibei Normal University He graduated from Huaibei Normal University in 1982, obtained the doctorate of science from Zhejiang University in 1999, and was promoted to Professor in 1993 From 1994 to 1995, visiting scholar of Western Kentucky University in the United States; from 1999 to 2001, he engaged in postdoctoral research in University of Tennessee atknoxville in the United States; from 2004 to 2005, visiting professor of Mississippi State University in the United States He was vice president of Huaibei Normal University (1999-2004), President of Huaibei Normal University (2004-2012), Secretary of the University Party committee (2012-2019) It has been selected as the national candidates for the national special support plan of "leading talents in one million projects" and "one million talents in the new century project", the excellent young teachers funding plan of the Ministry of education, and the outstanding professional and technical talents of Anhui Province, enjoying the special allowance of the State Council Since 2001, it has been supported by NSFC for 9 consecutive times Won the first prize of natural science of Anhui Province and the second prize of natural science of the Ministry of education He is a member of the 26th, 27th, 28th, 29th and 30th sessions of the Chinese chemical society, a member of the organic chemistry discipline committee of the Chinese chemical society, a vice chairman of the 7th, 8th and 9th sessions of the Anhui Provincial Chemical Society, a member of the Teaching Steering Committee of the chemistry major of the Ministry of education, a member of the academic degree committee of the Anhui Provincial People's government, etc Prof Li Pinhua, Professor, master supervisor, Secretary of the Party committee of the school of chemistry and materials science From 1996 to 2000, he majored in chemistry in Huaibei Normal University; from 2000 to 2004, he served as the teacher and assistant professor of the Department of chemistry in Huaibei Normal University; from 2005 to 2007, he served as the lecturer of the Department of chemistry in Huaibei Normal University; from 2007 to 2011, he served as the associate professor of the school of chemistry and material science in Huaibei Normal University; since October 2011, he has served as the professor of the school of chemistry and material science in Huaibei Normal University, and he is an academic and technical professor in Anhui Province Leader, advanced worker of Anhui Province, winner of Anhui outstanding youth science and Technology Innovation Award, advanced individual of teaching ethics of Anhui education system, new comer of Anhui education, enjoying special allowance of the State Council He has won the first prize of natural science of Anhui Province and the second prize of natural science of the Ministry of education Presided over the research of NSFC and NSFC of Anhui Province Zou long, the first author of this article In 2012, he was admitted to Huaibei Normal University and obtained his Bachelor of Science Degree in 2016 In 2017, he was admitted to Huaibei Normal University to study for master's degree under the guidance of Professor Wang Lei and Professor Li Pinhua Prof Wang Lei introduction to the research group The research group has been engaged in the development of a series of new organic synthesis reactions induced by visible light for a long time At present, we have successfully developed the visible light induced coupling reactions based on decarboxylation (carbonyl) and desulfonation without additional sensitizer, and through these reactions, we can efficiently construct functional organic molecules with potential biological activity under mild reaction conditions The research group adheres to the concept of green, safe and efficient synthesis, and constantly explores new methods of organic synthesis Front research achievements: visible light catalyzed synthesis of trifluoromethyl dihydroisoquinolinone dihydroisoquinolinone in aqueous phase by n-allylbenzamide and CF 3so2na at room temperature is the skeleton of a class of important drug molecules, which has attracted much attention in organic synthesis However, most of the methods reported in the literature have some disadvantages, such as expensive reagents, less green reaction conditions, and poor product yield In order to solve these problems, Professor Wang Lei and Professor Li Pinhua's research group reported a one-step strategy for the synthesis of trifluoromethyl dihydroisoquinolone in the presence of visible light induced photocatalyst in water medium using n-allylbenzamide and CF 3so2na (Langlois reagent) (Figure 1) Figure 1 Visible light induced cyclization of n-allylbenzamide to 3, 4-dihydroisoquinolinone (source: Green Chemistry) the authors selected n-allyl-n-methoxybenzamide (1a) and sodium trifluoromethylsulfite (cf3so2na, Langlois reagent) as model substrates, tert butyl hydrogen peroxide (TBHP, 70% H 2O solution) as free radical initiator, and selected photocatalyst , oxidant, solvent and light source to explore the best reaction conditions The results show that the target product 3A (Table 1, entry 8) can be obtained with 89% separation yield under the optimal conditions Table 1 Condition screening (source: Green Chemistry) under the optimal conditions, the author studied the substrate application range of the method (Figure 2) The selected substrates all obtained the target product in good yield, and the reaction selectivity was very high The X-ray single crystal diffraction analysis of the product 3S was carried out, and the correctness of the product structure was further confirmed Figure 2 Substrate expansion (source: Green Chemistry) Then, the author explored the reaction process through control experiments (Figure 3) At the same time, the cyclized product was applied to the subsequent functional group transformation experiments, which showed that the MEO protecting group could be removed (Fig 4) Figure 3 Control experiment (source: Green Chemistry) Figure 4 Functional group transformation experiment (source: Green Chemistry) According to the experimental results and literature reports, the author proposed the mechanism of the reaction (Figure 5) First, [Ru (bpy) 3] 2 + is activated to its excited state [Ru (bpy) 3] 2 + *, under visible light irradiation Next, TBHP obtains energy from the excited [Ru (bpy) 3] 2 + * (energy transfer process), and generates hydroxyl and tert butoxy through the decomposition of peroxide bond Then CF 3 radical (a) was formed by the reaction of TERT butoxy or hydroxyl with CF 3So 2Na Then, the obtained CF 3 group (a) is added to the double bond of n-allylbenzamide (1a) to obtain the free radical intermediate (b), which is then intramolecular cyclized to obtain the free radical intermediate (c) The formed C is oxidized by TERT butoxy or hydroxyl, and the cation intermediate (d) is produced by set process Finally, D loses protons to produce the desired product 3a, while forming water or TERT butanol Fig 5 Possible reaction mechanism (source: Green Chemistry) To sum up, our team has developed a green, efficient and simple visible light catalysis to obtain various dihydroisoquinolinone compounds from n-allylbenzamide and easily obtained sodium trifluoromethylsulfite (cf3so2na) In this reaction, the corresponding trifluoromethyl dihydroisoquinolinone was produced with high yield, which had good functional group tolerance under mild conditions This achievement was recently published in green chemistry (DOI: 10.1039 / c9gc00938h), with Zou long as the first author of the article, Professor Wang Lei and Professor Li Pinhua as the corresponding authors Thanks to NSFC (21772062, 21572078) and Anhui Distinguished Youth Fund (170808j02) for their financial support Nowadays, people and scientific research have been paid more and more attention in the economic life China has ushered in the "node of science and technology explosion" Behind the progress of science and technology is the work of countless scientists In the field of chemistry, in the context of the pursuit of innovation driven, international cooperation has been strengthened, the influence of Returned Scholars in the field of R & D has become increasingly prominent, and many excellent research groups have emerged in China For this reason, CBG information adopts the 1 + X reporting mechanism CBG information, chembeangoapp, chembeango official microblog, CBG wechat subscription number and other platforms jointly launch the column of "people and scientific research", approach the domestic representative research group, pay attention to their research, listen to their stories, record their demeanor, and explore their scientific research spirit.