Professor Wu Jie, Fudan University Research Group: sulfonation of ortho-c-h bond of aniline by sulfur dioxide insertion without metal

Lead: sulfur dioxide is the most common sulfur oxide and one of the main pollutants in the atmosphere, which is closely related to the formation of haze In addition, sulfur dioxide is also the main cause of acid rain, and comprehensive treatment of its pollution is one of the important research contents of environmental chemistry Sulfonyl segment (- SO2 -) is a very important group, which widely exists in drug molecules, pesticide molecules and material molecules The synthesis of sulfonyl compounds has been highly valued by chemists In recent years, the synthesis of sulfonyl compounds such as sulfonamides and sulfones has also made a lot of progress At present, the synthesis methods are mainly based on the existing sulfonyl segment substrates, such as sulfonyl chloride, sulphite, sulphite, sulfonic acid and so on The synthesis methods of these compounds are usually complicated, and the substrates have great limitations There is no doubt that it is the best choice from the point of view of synthesis if sulfonyl segments can be introduced through sulfur dioxide (SO2), a simple raw material In recent years, with the application of some sulfur dioxide substitutes such as DABCO · (SO2) 2 and sulfite, the insertion reaction of sulfur dioxide has developed rapidly In recent years, Professor Wu Jie's research group of Fudan University has paid close attention to the insertion reaction of sulfur dioxide in recent years, discovered several free radical transformation processes and achieved a series of good results (such as: angelw Chem Int ed., 2014, 53, 2451; angelw Chem Int ed., 2016, 55, 11925; review: org Chem Front., 2018, 5, 691; book: "sulfur dioxide Insertion Reactions forOrganic Synthesis ” , Nature Springer: Berlin,  2017 ）。 Introduction to the research group of Professor Wu Jie on the insertion reaction of sulfur dioxide At present, there are 1 postdoctoral student, 5 doctoral students and 2 master students in the research group In the early stage of the research group, the synthesis methodology, combinatorial chemistry and pharmaceutical chemistry based on the dominant skeleton of natural products are involved At present, the application of sulfur dioxide insertion in organic synthesis and pharmaceutical synthesis is mainly concerned We warmly welcome postdoctoral and graduate students who are interested in organic chemistry to join the research group Introduction to Professor Wu Jie, professor and doctoral supervisor of Fudan University From 1991 to 1995, he studied in the Department of chemistry of Jiangxi Normal University, and from 1995 to 2000, he studied as a postgraduate in Shanghai Institute of organic chemistry, Chinese Academy of Sciences (he obtained his doctor's degree in 2000) From 2000 to 2004, he successively studied in Harvard University (postdoctoral), Allen Damond AIDS research center of Rockefeller University (visiting scientist) and vivoquest, Inc (researcher) is engaged in organic synthesis, pharmaceutical chemistry and related research In September 2004, he returned to China and joined the Department of chemistry of Fudan University (Associate Professor) In April 2006, he was promoted to professor At present, the main research fields are: Construction of natural like small molecular compounds for anti-tumor and anti-virus drug research In 2007, he was selected into the Ministry of education's "new century talent support plan" and Shanghai's "Pujiang talent plan", in 2010, he was awarded "Thieme Chemistry Journals Award", in 2013, he was awarded "do Innovation Challenge Award", and in 2014-2017, he was successively selected into Elsevier's "highly cited" scholars list in China At present, he is the editorial board (ACS combinatorial science) of American Chemical Society, the young editorial board of China Chemical express, and the member of organic chemistry Professional Committee of Shanghai Chemical Society Since his independent work, he has published more than 260 SCI papers, cited more than 11000 times, participated in the preparation of four monographs, wrote one monograph, and obtained 2 US invention patents and 7 Chinese invention patents Frontier research results: under the condition of no metal, sulfur dioxide insertion is used to realize the C-H bond sulfonylation of aniline as an important organic synthesis precursor, which is often used as an effective target for the design and synthesis of drugs and bioactive molecules At present, there are many methods to synthesize aromatic amines, among which the functionalization of the ortho-c (SP 2) - H bond of aromatic amines with transition metal catalysts has become a powerful tool to produce a variety of aniline Recently, more and more attention has been paid to the functionalization of C-H bonds of aromatic amines via visible light induced radical processes Various functional groups can introduce aromatic rings of aniline under mild conditions through radical processes In recent years, Professor Wu Jie's research group at Fudan University has found that carbon radicals and DABCO • (SO 2) 2 or sulfite can effectively generate sulfonyl radicals, which can be used to synthesize various sulfonyl compounds Based on the above research background, the author started from simple aniline, functionalized C-H bond of aniline under non-metallic conditions, and constructed 2-sulfonylaniline compounds with high efficiency The group designed three component reactions of aniline substrate with aryldiazonium salt and DABCO · (SO 2) 2 The reaction does not need to add metal catalyst and other additives The reaction conditions are mild, the substrate has good universality, and halogen, ester group and nitro group are well compatible In addition to N, N-disubstituted aniline, N-monosubstituted aniline can also obtain the target product in medium yield For p-unsubstituted aniline, p-sulfonylation products can also be obtained Figure 1 Investigation of substrate range (source: Chemical Communications) Figure 2 Further expansion of substrate range to 1b and 1C (source: Chemical Communications) Based on the previous research and corresponding mechanism verification experiments of the research group, the author proposed two possible reaction mechanisms: aryldiazonium salt and DABCO • (SO 2) 2 In situ, arylsulfonyl radical and tertiary amino radical cation are produced The tertiary amino radical cation and aniline undergo a single electron transfer (set) to produce free radical cation B and release DABCO (path a) Free radical cation B is tautomerized to give free radical cation C, which is coupled with arylsulfonyl a to form intermediate D Then 2-sulfonylaniline 3 was obtained by deprotonation and aromatization Alternatively, arylsulfonyl radical a attacks aniline to produce free radical e (path B) Then, the tertiary amine radical cation will participate in the single electron transfer to promote the formation of cation intermediate F, and finally the final product 3 will be obtained by deprotonation Figure 3 Possible reaction mechanism (source: Chemical Communications) Summary: the research group designed the three-component reaction of aniline, aryldiazonium salt and DABCO • (SO 2) 2 under the condition of metal free, and realized the sulfonation of C-H bond of aniline by sulfur dioxide insertion Under mild conditions, 2-sulfonylaniline was synthesized in good yield The conversion conditions are mild, high selectivity and good functional group compatibility This achievement was recently published in chemical communications (DOI: 10.1039 / c8cc03465f) The authors are Kaida Zhou, Jun Zhang, Lifang Lai, Jiang Cheng, Jiangtao sun, Jie Wu previous reports of Professor Wu Jie of Fudan University: the project team of Professor Wu Jie of Fudan University realized the visible light catalytic synthesis of alkylsulfonyl compounds by three components reaction of three components of potassium alkylfluoroborate, sulfur dioxide and olefin Today, science and technology elements are increasingly valued in 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.