Divergent Synthesis of Sulfur-Containing Bridged Cyclobutanes by Lewis Acid Catalyzed Formal Cycloadditions of Pyridinium 1,4-Zwitterionic Thiolates and Bicyclobutanes
Yuanjiu Xiao
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorFeng Wu
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorLei Tang
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorDr. Xu Zhang
School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, 225002 P.R. China
Search for more papers by this authorMengran Wei
Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093 P. R. China
Search for more papers by this authorCorresponding Author
Prof. Dr. Guoqiang Wang
Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093 P. R. China
Search for more papers by this authorCorresponding Author
Prof. Dr. Jian-Jun Feng
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorYuanjiu Xiao
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorFeng Wu
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorLei Tang
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorDr. Xu Zhang
School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, 225002 P.R. China
Search for more papers by this authorMengran Wei
Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093 P. R. China
Search for more papers by this authorCorresponding Author
Prof. Dr. Guoqiang Wang
Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093 P. R. China
Search for more papers by this authorCorresponding Author
Prof. Dr. Jian-Jun Feng
State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082 P. R. China
Search for more papers by this authorGraphical Abstract
A divergent synthesis of two types of sulfur-containing bridged cyclobutanes, 2-thia-5-azabicyclo[5.1.1]nonenes and thia-norpinenes from identical bicyclobutanes (BCBs), respectively, through high-order(5+3) and hetero-(3+3) reactions, has been developed.
Abstract
Bridged cyclobutanes and sulfur heterocycles are currently under intense investigation as building blocks for pharmaceutical drug design. Two formal cycloaddition modes involving bicyclobutanes (BCBs) and pyridinium 1,4-zwitterionic thiolate derivatives were described to rapidly expand the chemical space of sulfur-containing bridged cyclobutanes. By using Ni(ClO4)2 as the catalyst, an uncommon higher-order (5+3) cycloaddition of BCBs with quinolinium 1,4-zwitterionic thiolate was achieved with broad substrate scope under mild reaction conditions. Furthermore, the first Lewis acid-catalyzed asymmetric polar (5+3) cycloaddition of BCB with pyridazinium 1,4-zwitterionic thiolate was accomplished. In contrast, pyridinium 1,4-zwitterionic thiolates undergo an Sc(OTf)3-catalyzed formal (3+3) reaction with BCBs to generate thia-norpinene products, which represent the initial instance of synthesizing 2-thiabicyclo[3.1.1]heptanes (thia-BCHeps) from BCBs. Moreover, we have successfully used this (3+3) protocol to rapidly prepare thia-BCHeps-substituted analogues of the bioactive molecule Pitofenone. Density functional theory (DFT) computations imply that kinetic factors govern the (5+3) cycloaddition reaction between BCB and quinolinium 1,4-zwitterionic thiolate, whereas the (3+3) reaction involving pyridinium 1,4-zwitterionic thiolates is under thermodynamic control.
Conflict of Interests
The authors declare no conflict of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available in the supplementary material of this article.
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