Professor Wu Lei, Nanjing Agricultural University Research Group: binanyl nano palladium catalyzed Alkynylation and highly selective hydrogenation in series to construct phosphoryl (z) - [3] dendrarenes

In recent years, as a kind of acyclic cross conjugated oligoolefins, dendralenes has attracted more and more attention due to its unique structure and application value Although (z) - [3] dendralenes are widely found in natural products such as plant essential oil and bilirubin, its stereoselective synthesis is still the most challenging field, especially the synthesis method of (Z, z) - [3] dendralenes has only two reports at present, but its stereoselectivity is poor or its yield is low Advanced synthesis & catalyst, 2016, 358, 3039; catalyst Science & technology, 2017, 7, 5515) and phosphoryl [3] dendralenes (ACS catalyst sis, 2017, 7, Based on the research of (181), the series Alkynylation and highly selective hydrogenation of (z) and (Z, z) - [3] dendralenes with binaryl palladium nanocatalyst were successfully developed In addition, this paper has carried out a variety of derivative studies on (z) - [3] dendralenes Related work was published in org Lett (DOI: 10.1021 / ACS Orglett 9b02287) Brief introduction of Professor Wu Lei's research group in recent years, Professor Wu Lei's research group has focused on the synthesis methods of functional organophosphorus compounds and heterocyclic compounds and nano catalytic materials, etc., in ACS catalyst, org Lett., chem Commun., org Chem Front., adv synth Catalyst., catalyst SCI Technol., J org Chem, Chem EUR J and other international journal systems published many achievements Prof Wu Lei, born in 1980, professor and doctoral supervisor of Nanjing Agricultural University, vice president of School of science In 2007, he graduated from the Institute of chemistry, Chinese Academy of Sciences, under the guidance of researcher fan Qinghua From 2007 to 2010, he was engaged in postdoctoral research in Syracuse University and University of Notre Dame in the United States From 2010 to 2012, he worked in the Institute of basic and interdisciplinary sciences of Harbin University of Technology (introduced by Harbin University of technology's "hundred talents plan"), and entered Nanjing Agricultural University in August 2012 It has been selected as the "blue and blue project" of Jiangsu Province, the "333 high-level talent training project" of Jiangsu Province and the "excellent graduate teacher" of Nanjing Agricultural University The main research fields are heteroatom chemistry and metal nano catalysis materials He has successively presided over many scientific research projects, such as the National Natural Science Foundation of China, Jiangsu Natural Science Foundation, the research start-up project of returned overseas students of the Ministry of education, the start-up fund of high-level talents introduction of Nanjing Agricultural University, and the start-up fund of talents introduction of Harbin University of industry He has been in ACS catalyst, org Lett., chem Commin., J org Chem., chem EUR J., adv synth Catalyst., catalyst SCI Technology And other international authoritative journals published more than 40 SCI papers by corresponding authors, with H index of 20, he cited more than 1000 times, and 3 research papers were selected into "ESI high cited papers" He is the reviewer of SCI journals at home and abroad, such as organic chemistry, Journal of chemistry, ACS catalyst, green chem., org Lett., adv synth Catalyst., chem EUR J Leading scientific research achievements: binanyl nano palladium catalyzes Alkynylation and highly selective hydrogenation in series to build phosphoryl (z) - [3] dentralenes as shown in Figure 1 The author first attempts to optimize the reaction under the condition of hydrogen balloon, using 2 mol% bin pdnps (binanyl nano palladium) as catalyst, taking phosphine to replace diene (1a) and phenylacetylene as substrates As shown in Figure 2, solvents and bases play an important role in the reaction The optimum conditions were found in DMF and the target product 2a was obtained in 83% yield At the same time, the products 2A 'and 2A "of further hydrogenation were observed in the process of condition exploration It is worth mentioning that both heterogeneous Lindlar and Pd / C catalysts have no catalytic activity for the series reaction Although PD (PPh3) 4 and Pd (PPh3) 2Cl2 obtained a certain amount of 2a, their catalytic efficiency and regioselectivity could not be controlled Fig 1 bin pdnps catalyses the series reaction of Phos substituted diene with phenylacetylene (source: org Lett.) Fig 2 condition screening (source: org Lett.) after determining the optimal reaction conditions, the author first studied the applicability of alkyne substrate (Fig 3) Generally, for arylalkynes, the electron donating effect is observed When the para substituent of arylalkyne has electron donating group (such as methyl, ethyl, tert butyl, phenyl and methoxy), the reaction can get quite good yield (2b-f), especially, when the para is methoxy, the reaction can get 91% yield When there are electron absorbing substituents on the aryl group, including P-F, p-cn and p-no2, it is not conducive to the occurrence of the reaction, and only the medium yield can be obtained When the p-position is phenyl, the yield may be reduced due to the steric hindrance At the same time, when the para group is ester group, 80% yield can also be obtained The mild and high selectivity of the reaction can also be explained by the substrate with nitro group, which can be maintained in the final product (2J) It is worth mentioning that this method can also be applied to heteroaromatic alkynes, and 3-pyridyl and 2-thiophenyl alkynes can also be obtained in medium to good yields (2m and 2n), so as to obtain a new kind of heterocyclic substituted dendrarenes Aliphatic alkynes, such as isopropenylacetylene and 1-octyne, can also react It is worth noting that in the case of isopropenylacetylene, the distal non conjugate double bond is also hydrogenated to obtain compound 2O in 72% yield Fig 3 substrate universality study (source: org Lett.) next, the author studied the reaction of acyclic compounds at the end of diene The results showed that the corresponding products could be obtained with better yield and chemical selectivity It is worth mentioning that the change of R 1 and R 2 groups will generate Z, Z - [3] dendralenes When unsymmetrical p-o-substituted dienes are used to react with aromatic alkynes without substituents, the target products of Z, Z configuration can be obtained with high chemical selectivity When the arylalkynes contain electron acceptors, such as fluorine substitution, the selectivity is significantly reduced However, when the arylalkynes contain electron acceptors, such as p-methoxyphenyl and β - naphthyl alkyne substrates, the proportion of Z and Z configuration of the corresponding products is increased The stereoselectivity of phos-o-substituted diene is very poor when the terminal of phos-o-substituted diene contains asymmetric chain alkyl Fig 4 substrate universality study (source: org Lett.) in order to further prove the potential application value of the reaction, the author conducted gram scale-up of the reaction and carried out a variety of derivative studies of (z) - [3] dendralenes (Fig 5) Fig 5 gram level reaction and product derivatization (source: org Lett.) to sum up, based on the high-efficiency catalytic ability of binanyl palladium nano catalyst (bin pdnps), the author developed a new high-efficiency selective synthesis strategy of phosphoryl-z and Z, Z - [3] dendralenes The Alkynylation and highly selective hydrogenation are carried out in series, which has good functional group tolerance and yield A series of Z - [3] dendralenes and Z, Z - [3] dendralenes were synthesized This method has the advantages of mild reaction conditions, simple operation and high chemical selectivity, which has expanded the synthesis method of dendralenes This achievement was recently published in organic letters (DOI: 10.1021/acs.orglett 9b02287) The research work is mainly completed by Xia Yuntao, a 2017 level doctoral candidate of Professor Wu Lei's research group, and assisted by other graduate students and undergraduates of the research group Professor Wu Lei is the corresponding author of the article The above research work has been supported by Jiangsu Natural Science Foundation, basic scientific research business fees of central universities, Jiangsu University Blue project, and Jiangsu Province "333 high level talent training project" 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 website, chembeangoapp, chembeango official micro blog, CBG information wechat subscription number and other platforms jointly launch the column of "people and scientific research", approach the representative research groups in China, pay attention to their research, listen to their stories, record their demeanor, and explore their scientific research spirit.