Monoarsacyclacenes of P and F types having 3～8 arenoid rings were considered for PM3 type semiempirical molecular orbital calculations. These, yet nonexistent structures, were expected to be endothermic but stable...Monoarsacyclacenes of P and F types having 3～8 arenoid rings were considered for PM3 type semiempirical molecular orbital calculations. These, yet nonexistent structures, were expected to be endothermic but stable molecules exhibiting no cryptoannulenic effect.展开更多
Recent years have witnessed breakthroughs in the study of zigzag hydrocarbon belts.However,the synthesis of heterocycle-containing zigzag molecular belts remains very rare and challenging despite their interesting str...Recent years have witnessed breakthroughs in the study of zigzag hydrocarbon belts.However,the synthesis of heterocycle-containing zigzag molecular belts remains very rare and challenging despite their interesting structures and potential applications in chemistry and materials science.Here,we report the expeditious construction of a highly strained belt[4]arene[4](1,4-dihydropyridine)structure using the fjords-stitching strategy.The synthesis comprised four-fold abnormal m-bromination of four Npivaloylaniline units and Pd_(2)(dba)_(3)/4-Me_(2)NC_(6)H_(4)Pt Bu_(2)-catalyzed intramolecular C-N bond-forming reactions.Subsequent functionalization through Narylations produced a variety of tetraza-embedded octahydrobelt[8]arenes.Further oxidation of p-methoxyphenyl-substituted belt[4]arene[4](1,4-dihydropyridine)with Ag[Al(O^(t)Bu^(F))^(4)]yielded a singlet diradical dication N-doped zigzag belt.展开更多
Zigzag hydrocarbon belts have been fascinating chemists and materials scientists for decades because of their aesthetically appealing molecular structures,outstanding physical properties and intriguing chemical reacti...Zigzag hydrocarbon belts have been fascinating chemists and materials scientists for decades because of their aesthetically appealing molecular structures,outstanding physical properties and intriguing chemical reactivities predicted by theoretical calculations,and potential applications as unique macrocyclic hosts in supramolecular chemistry.They may also serve as templates or seeds to grow structurally well-defined uniform zigzag carbon nanotubes.While there have been continuous computational studies on the structures and properties of belt[n]arenes or[n]cyclacenes since they were proposed as hypothetical molecules in 1954,the synthesis of(partially)conjugated zigzag hydrocarbon belts remains a great challenge,with no progress being reported in the past 20 years.Very recently,we have been witnessing the renaissance of synthetic interest in zigzag hydrocarbon belts,and the formation of the first fully conjugated one is on the horizon.This minireview focuses on the understanding of belt[n]arenes based on theoretical calculations and the synthesis and structure of zigzag hydrocarbon belts.Perspectives on the strategies to isolate and characterize the fully conjugated belt[n]arenes and on the applications of zigzag hydrocarbon belts are also discussed.展开更多
文摘Monoarsacyclacenes of P and F types having 3～8 arenoid rings were considered for PM3 type semiempirical molecular orbital calculations. These, yet nonexistent structures, were expected to be endothermic but stable molecules exhibiting no cryptoannulenic effect.
基金We thank the National Natural Science Foundation of China(grant nos.22050005,21732004,and 21821001)the Tsinghua University Initiative Scientific Research Program(grant no.2019Z07L01004)for generous financial support.
文摘Recent years have witnessed breakthroughs in the study of zigzag hydrocarbon belts.However,the synthesis of heterocycle-containing zigzag molecular belts remains very rare and challenging despite their interesting structures and potential applications in chemistry and materials science.Here,we report the expeditious construction of a highly strained belt[4]arene[4](1,4-dihydropyridine)structure using the fjords-stitching strategy.The synthesis comprised four-fold abnormal m-bromination of four Npivaloylaniline units and Pd_(2)(dba)_(3)/4-Me_(2)NC_(6)H_(4)Pt Bu_(2)-catalyzed intramolecular C-N bond-forming reactions.Subsequent functionalization through Narylations produced a variety of tetraza-embedded octahydrobelt[8]arenes.Further oxidation of p-methoxyphenyl-substituted belt[4]arene[4](1,4-dihydropyridine)with Ag[Al(O^(t)Bu^(F))^(4)]yielded a singlet diradical dication N-doped zigzag belt.
基金the National Science Foundation of China(grant nos.21732004,21821001,and 91427301)Tsinghua University Initiative Scientific Research Program for financial support.
文摘Zigzag hydrocarbon belts have been fascinating chemists and materials scientists for decades because of their aesthetically appealing molecular structures,outstanding physical properties and intriguing chemical reactivities predicted by theoretical calculations,and potential applications as unique macrocyclic hosts in supramolecular chemistry.They may also serve as templates or seeds to grow structurally well-defined uniform zigzag carbon nanotubes.While there have been continuous computational studies on the structures and properties of belt[n]arenes or[n]cyclacenes since they were proposed as hypothetical molecules in 1954,the synthesis of(partially)conjugated zigzag hydrocarbon belts remains a great challenge,with no progress being reported in the past 20 years.Very recently,we have been witnessing the renaissance of synthetic interest in zigzag hydrocarbon belts,and the formation of the first fully conjugated one is on the horizon.This minireview focuses on the understanding of belt[n]arenes based on theoretical calculations and the synthesis and structure of zigzag hydrocarbon belts.Perspectives on the strategies to isolate and characterize the fully conjugated belt[n]arenes and on the applications of zigzag hydrocarbon belts are also discussed.
