Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(...Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.展开更多
The title compound l-benzyl-5-（（4-methoxyphenyl）ethynyl）-4-phenyl-1H-1,2,3-triazole（C24H19N3O） was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray...The title compound l-benzyl-5-（（4-methoxyphenyl）ethynyl）-4-phenyl-1H-1,2,3-triazole（C24H19N3O） was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray diffraction,NMR,IR and MS.This compound was crystallized out from an ethanolic solution in triclinic system,space group P1 with a =9.9038（9）,b = 10.2928（9）,c = 18.8715（19）A°,α = 103.541（6）,β = 90.507（7）,γ = 97.157（7）°,V =1854.2（3） A°3,Z = 4,crystal size（mm） = 0.25 × 0.1 × 0.1 and R（int） = 0.068.Its asymmetric unit contains two independent molecules.The crystal structure of the title compound is stabilized by intramolecular interactions of types C-H…N and C-H…O.Additionally,X-ray analysis reveals obvious C-H…π,π-π stacking interactions between two adjacent aromatic ring planes.展开更多
By rational modification of electronic and steric properties of pincer ligands,a Co/Fe dual catalyst system is developed for one-pot sequential Markovnikov alkyne hydrosilylation and stereoselective alkene isomerizati...By rational modification of electronic and steric properties of pincer ligands,a Co/Fe dual catalyst system is developed for one-pot sequential Markovnikov alkyne hydrosilylation and stereoselective alkene isomerization.The protocol provides an atom-economical and efficient approach to trisubstituted(E)-alkenyl silanes from widely accessible terminal alkynes with high regio-and stereoselectivities under mild conditions.The utility of this reaction was demonstrated by gram-scale synthesis and derivatization of bioactive molecules.The radical clock and trapping experiments indicated that radical pathway might be operative in the alkene isomerization step.展开更多
In recent years,the synthesis and application of alkenes have attracted increased attention.Triphenylethenes(TriPEs)have lower molecular torsion than tetraphenylethenes(TPEs),which helps to balance the degree of conju...In recent years,the synthesis and application of alkenes have attracted increased attention.Triphenylethenes(TriPEs)have lower molecular torsion than tetraphenylethenes(TPEs),which helps to balance the degree of conjugation and the aggregation-induced emission(AIE)effect.The geometry of double bonds has a significant impact on luminescence.Therefore,it is essential to provide a comprehensive summary of the stereoselective synthetic strategies for trisubstituted alkenes.In this review,common strategies for the stereoselective synthesis of alkenes are described,with an emphasis on the origin of stereoselectivity and the types of substrates.In addition,the AIE properties of TriPE and its applications in optoelectronic devices,stimuli-responsive materials,sensors,and therapies were discussed.展开更多
In this paper, the reaction of 1, 2, 3-trisubstituted electron-deficient cyclopropane derivatives ets-1-benzoyl-2-p-substituted phenyl-6, 6-dimethyl-5, 7-dioxo-spiro-[2,5]-4, 8-octadiones with methanol was studied. Th...In this paper, the reaction of 1, 2, 3-trisubstituted electron-deficient cyclopropane derivatives ets-1-benzoyl-2-p-substituted phenyl-6, 6-dimethyl-5, 7-dioxo-spiro-[2,5]-4, 8-octadiones with methanol was studied. The structures of the reaction products were confirmed as methyl β-benzoyl-γ-methoxy-γ-p- substituted phenylbutyrates by means of IR, MS, microanalysis, IH, 13C NMR spectroscopies and APT techniques. The reaction mechanism for the formation of the product was also proposed.展开更多
文摘Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.
基金supported by the Higher Education Commision(HEC),Govt.of Pakistan
文摘The title compound l-benzyl-5-（（4-methoxyphenyl）ethynyl）-4-phenyl-1H-1,2,3-triazole（C24H19N3O） was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray diffraction,NMR,IR and MS.This compound was crystallized out from an ethanolic solution in triclinic system,space group P1 with a =9.9038（9）,b = 10.2928（9）,c = 18.8715（19）A°,α = 103.541（6）,β = 90.507（7）,γ = 97.157（7）°,V =1854.2（3） A°3,Z = 4,crystal size（mm） = 0.25 × 0.1 × 0.1 and R（int） = 0.068.Its asymmetric unit contains two independent molecules.The crystal structure of the title compound is stabilized by intramolecular interactions of types C-H…N and C-H…O.Additionally,X-ray analysis reveals obvious C-H…π,π-π stacking interactions between two adjacent aromatic ring planes.
基金the National Key R&D Program of China(2021YFA1500100)the National Natural Science Foundation of China(21825109,21821002,22072178,22293013)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0610000)CAS Project for Young Scientists in Basic Research(YSBR-094)Science and Technology Commission of Shanghai Municipality(23JC1404400)CAS Youth Interdisciplinary Team(JCTD-2021-11).
文摘By rational modification of electronic and steric properties of pincer ligands,a Co/Fe dual catalyst system is developed for one-pot sequential Markovnikov alkyne hydrosilylation and stereoselective alkene isomerization.The protocol provides an atom-economical and efficient approach to trisubstituted(E)-alkenyl silanes from widely accessible terminal alkynes with high regio-and stereoselectivities under mild conditions.The utility of this reaction was demonstrated by gram-scale synthesis and derivatization of bioactive molecules.The radical clock and trapping experiments indicated that radical pathway might be operative in the alkene isomerization step.
基金supported by the National Natural Science Foundation of China(81874181,21871284)the Major Scientific and Technological Special Project for“Significant New Drugs Creation”(2019ZX09301158)+2 种基金the Emerging Frontier Program of Hospital Development Centre(SHDC12018107)the Science&Technology Department of Shanghai(18401933500)the State Key Laboratory of Bioorganic and Natural Products Chemistry。
文摘In recent years,the synthesis and application of alkenes have attracted increased attention.Triphenylethenes(TriPEs)have lower molecular torsion than tetraphenylethenes(TPEs),which helps to balance the degree of conjugation and the aggregation-induced emission(AIE)effect.The geometry of double bonds has a significant impact on luminescence.Therefore,it is essential to provide a comprehensive summary of the stereoselective synthetic strategies for trisubstituted alkenes.In this review,common strategies for the stereoselective synthesis of alkenes are described,with an emphasis on the origin of stereoselectivity and the types of substrates.In addition,the AIE properties of TriPE and its applications in optoelectronic devices,stimuli-responsive materials,sensors,and therapies were discussed.
文摘In this paper, the reaction of 1, 2, 3-trisubstituted electron-deficient cyclopropane derivatives ets-1-benzoyl-2-p-substituted phenyl-6, 6-dimethyl-5, 7-dioxo-spiro-[2,5]-4, 8-octadiones with methanol was studied. The structures of the reaction products were confirmed as methyl β-benzoyl-γ-methoxy-γ-p- substituted phenylbutyrates by means of IR, MS, microanalysis, IH, 13C NMR spectroscopies and APT techniques. The reaction mechanism for the formation of the product was also proposed.
