Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The s...Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been synthesized.The m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar method.All of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.展开更多
A novel water-soluble, phosphine-free PEG ＂click＂ triazole palladacycle has been successfully synthesized. As a precatalyst, the palladacycle exhibited superior catalytic activity towards Suzuki-Miyaura and copper-f...A novel water-soluble, phosphine-free PEG ＂click＂ triazole palladacycle has been successfully synthesized. As a precatalyst, the palladacycle exhibited superior catalytic activity towards Suzuki-Miyaura and copper-free Sonogashira cross-coupling in neat water with the turnover numbers （TONs） of up to 9.8 × 10^5. In addition, the cata- lyst could be reused at least 3 times without significant loss of reactivity.展开更多
An efficient palladacycle-catalyzed aromatic carbonylation reaction of aryl formates with aryl iodides or bromides has been developed. Commercially available and easily prepared aryl formates were employed as carbonyl...An efficient palladacycle-catalyzed aromatic carbonylation reaction of aryl formates with aryl iodides or bromides has been developed. Commercially available and easily prepared aryl formates were employed as carbonyl sources without the use of external carbon monoxide. The present catalytic system shows broad functional group tolerance and affords aryl benzoate derivatives in good to excellent yields.展开更多
Palladacycles remain a challenging and significant research field in organic chemistry and have emerged as a type of powerful and versatile precatalysts or key active intermediates for transition metal catalysis.These...Palladacycles remain a challenging and significant research field in organic chemistry and have emerged as a type of powerful and versatile precatalysts or key active intermediates for transition metal catalysis.These achievements in this area are correlated to the design and development of useful ancillary ligands,such as N-heterocyclic carbenes(NHCs),which not only stabilize the actual catalytic active species facilitating the transformations,but also provide additional control over the selectivity of reactions.In this context,NHCs-ligated palladacycles(NHCP_(dcycles))with different electronic and steric properties have been synthesized and applied as green precatalysts(high stability and activity,low catalyst loading and mild reaction conditions)to accelerate transition metalcatalyzed reactions.Therefore,this review focuses mainly on the strategy of NHC-Pd_(cycles) design and catalytic results obtained from representative transition metal catalysis,such as Suzuki-Miyaura,Heck-Mizoroki and Sonogashira cross-coupling reactions,Buchwald-Hartwig amination,carbonylation as well as arylation.At last,the current limitations and potential trends for further development of NHC-Pdcycles are also highlighted.展开更多
基金supported by the National Natural Science Foundation of China (Nos.22031003,21720102004)the Shanghai Science Technology Committee (No.19DZ2270100).
文摘Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been synthesized.The m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar method.All of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China （No. 20702051）, the Natural Science Foundation of Zhejiang Province （LY13B020017） and the Key Innovation Team of Science and Technology in Zhejiang Province （No. 2010R50018）.
文摘A novel water-soluble, phosphine-free PEG ＂click＂ triazole palladacycle has been successfully synthesized. As a precatalyst, the palladacycle exhibited superior catalytic activity towards Suzuki-Miyaura and copper-free Sonogashira cross-coupling in neat water with the turnover numbers （TONs） of up to 9.8 × 10^5. In addition, the cata- lyst could be reused at least 3 times without significant loss of reactivity.
基金We are grateful to the National Natural Science Foundation of China，the Education Department of Henan Province science and technology research projects (No.13A150681) for financial support of this research
文摘An efficient palladacycle-catalyzed aromatic carbonylation reaction of aryl formates with aryl iodides or bromides has been developed. Commercially available and easily prepared aryl formates were employed as carbonyl sources without the use of external carbon monoxide. The present catalytic system shows broad functional group tolerance and affords aryl benzoate derivatives in good to excellent yields.
基金Financial support from the National Natural Science Foundation of China(No.22101133)the Natural Science Foundation of Jiangsu Province(No.BK20200768)is greatly acknowledged.
文摘Palladacycles remain a challenging and significant research field in organic chemistry and have emerged as a type of powerful and versatile precatalysts or key active intermediates for transition metal catalysis.These achievements in this area are correlated to the design and development of useful ancillary ligands,such as N-heterocyclic carbenes(NHCs),which not only stabilize the actual catalytic active species facilitating the transformations,but also provide additional control over the selectivity of reactions.In this context,NHCs-ligated palladacycles(NHCP_(dcycles))with different electronic and steric properties have been synthesized and applied as green precatalysts(high stability and activity,low catalyst loading and mild reaction conditions)to accelerate transition metalcatalyzed reactions.Therefore,this review focuses mainly on the strategy of NHC-Pd_(cycles) design and catalytic results obtained from representative transition metal catalysis,such as Suzuki-Miyaura,Heck-Mizoroki and Sonogashira cross-coupling reactions,Buchwald-Hartwig amination,carbonylation as well as arylation.At last,the current limitations and potential trends for further development of NHC-Pdcycles are also highlighted.
