An efficient Pd/Cu-catalyzed oxidative self-carbonylation of arylhydrazine with CO and molecular oxygen as an oxidant to afford symmetrical biaryl ketones via C—N bond activation has been developed.In this approach,a...An efficient Pd/Cu-catalyzed oxidative self-carbonylation of arylhydrazine with CO and molecular oxygen as an oxidant to afford symmetrical biaryl ketones via C—N bond activation has been developed.In this approach,arylhydrazine hydrochlorides are used as a green arylating agent which releases nitrogen and water as byproducts.This developed protocol significantly restricts the formation of aryl iodide and homo-coupled azobenzene products even under favorable conditions.A library of symmetrical biaryl ketones with wide functionalities was synthesized in good yields under mild conditions.展开更多
To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization（N（sp2）） involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium m...To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization（N（sp2）） involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium macrocycles, namely cyclo[2]（2,6-bis-（1H-imidazol-1-yl）pyridine） [2]（1,3-dimethylenebenzene）（14＋）, and cyclo[2]（2,6-bis-（1H-imidazol-1-yl）pyridine）[2]（2,6-di methylenepyridine）（24＋）were studied in detail as small inorganic anion receptors. The guest anions with different shapes are Cl,N3, NO3, and H2PO4. The host–guest interactions were characterized via1 H NMR spectroscopy,electrospray ionization mass spectrometry（ESI-MS） and single crystal X-ray crystallography. The results implied that macrocyclic hosts with similar backbone but two distinct binding sites（14＋with neutral C–H vs. 24＋with N（sp2）） vary markedly in their response to anions, including the binding modes and association constants. The finding will serve to the construction of new anion receptors, even improve insights into the anion binding process in biology.展开更多
A novel copper-catalyzed direct C–N formation reaction of simple arenes with cheap and pharmacological saccharin derivatives under relatively mild conditions was developed with arenes as limiting reagents.This work p...A novel copper-catalyzed direct C–N formation reaction of simple arenes with cheap and pharmacological saccharin derivatives under relatively mild conditions was developed with arenes as limiting reagents.This work provided a new method for oxidative coupling of aromatic C(sp2)–H bonds and N–H bonds.展开更多
基金Y.A.Kolekar gratefully acknowledges the University Grants Commission(UGC)(New Delhi,India,for the Senior Research Fellowship(SRF)We acknowledge financial support from the DST-sponsored project No.DST/INT/RUS/RSF/P-54/2021.
文摘An efficient Pd/Cu-catalyzed oxidative self-carbonylation of arylhydrazine with CO and molecular oxygen as an oxidant to afford symmetrical biaryl ketones via C—N bond activation has been developed.In this approach,arylhydrazine hydrochlorides are used as a green arylating agent which releases nitrogen and water as byproducts.This developed protocol significantly restricts the formation of aryl iodide and homo-coupled azobenzene products even under favorable conditions.A library of symmetrical biaryl ketones with wide functionalities was synthesized in good yields under mild conditions.
基金financially supported by the National Natural Science Foundation of China (No. 21202199 to Han-Yuan Gong, and No. 21372258 to Li-Jin Xu)
文摘To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization（N（sp2）） involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium macrocycles, namely cyclo[2]（2,6-bis-（1H-imidazol-1-yl）pyridine） [2]（1,3-dimethylenebenzene）（14＋）, and cyclo[2]（2,6-bis-（1H-imidazol-1-yl）pyridine）[2]（2,6-di methylenepyridine）（24＋）were studied in detail as small inorganic anion receptors. The guest anions with different shapes are Cl,N3, NO3, and H2PO4. The host–guest interactions were characterized via1 H NMR spectroscopy,electrospray ionization mass spectrometry（ESI-MS） and single crystal X-ray crystallography. The results implied that macrocyclic hosts with similar backbone but two distinct binding sites（14＋with neutral C–H vs. 24＋with N（sp2）） vary markedly in their response to anions, including the binding modes and association constants. The finding will serve to the construction of new anion receptors, even improve insights into the anion binding process in biology.
基金financially supported by the National Natural Science Foundation of China(21172033,21372041,21302017)
文摘A novel copper-catalyzed direct C–N formation reaction of simple arenes with cheap and pharmacological saccharin derivatives under relatively mild conditions was developed with arenes as limiting reagents.This work provided a new method for oxidative coupling of aromatic C(sp2)–H bonds and N–H bonds.
