Chinese Journal of Organic Chemistry ›› 2022, Vol. 42 ›› Issue (6): 1811-1819.DOI: 10.6023/cjoc202112041 Previous Articles     Next Articles



马丽文, 魏晓叶, 赵紫琳, 赵昂, 邓祥文, 霍丙南, 马刚, 张春芳*()   

  1. 河北大学化学与环境科学学院 河北保定 071002
  • 收稿日期:2021-12-30 修回日期:2022-01-25 发布日期:2022-02-17
  • 通讯作者: 张春芳
  • 基金资助:
    国家自然科学基金(11704024); 国家自然科学基金(21973024); 河北省自然科学基金(B2020201006); 河北大学人才引进项目(521000981133); 河北大学在读研究生创新能力培养(HBU2021ss021); 河北大学2021年课程思政教学改革研究(KCSZ21053); 河北大学第三批“精品实验项目”(2021-BZ-JPSY37); 河北大学大学生创新创业训练计划项目(2020281); 河北大学大学生创新创业训练计划项目(2021184); 河北大学化学与环境科学学院第二批本科教学改革(H2-04004); 河北大学化学与环境科学学院第二批本科教学改革(H2-06001)

Theoretical Study on the Catalytic Mechanism of Copper with Various Valence for the Terminal Alkyne Coupling Reaction

Liwen Ma, Xiaoye Wei, Zilin Zhao, Ang Zhao, Xiangwen Deng, Bingnan Huo, Gang Ma, Chunfang Zhang()   

  1. College of Chemistry & Environmental Science, Hebei University, Baoding, Hebei 071002
  • Received:2021-12-30 Revised:2022-01-25 Published:2022-02-17
  • Contact: Chunfang Zhang
  • Supported by:
    National Natural Science Foundation of China(11704024); National Natural Science Foundation of China(21973024); Natural Science Foundation of Hebei Province(B2020201006); Advanced Talents Incubation Program of the Hebei University(521000981133); Post-Graduate's Innovation Fund Project of Hebei University(HBU2021ss021); 2021 Curriculum Ideological and Political Education of Hebei University(KCSZ21053); Third Excellent Experimental Project of Hebei University(2021-BZ-JPSY37); College Studentsʼ Innovation and Entrepreneurship Training Program of Hebei University(2020281); College Studentsʼ Innovation and Entrepreneurship Training Program of Hebei University(2021184); Teaching and Reform Project of College of Chemistry & Environmental Science, Hebei University(H2-04004); Teaching and Reform Project of College of Chemistry & Environmental Science, Hebei University(H2-06001)

Copper-catalyzed homo-coupling reaction of terminal alkynes is of significant importance for the synthesis of conjugated diynes. Based on density functional theory and Marcus formula, the reaction mechanism for the copper-catalyzed homo-coupling reaction of phenylacetylene (PAY) is reported. Our calculations show that PAY is preferentially coordinated with the cuprous complexes in different organic solvents, which is transferred to Cu(II)-acetylide (complex 1) by single electron transfer reaction. Complex 1 is subsequently transferred to Cu(I)-acetylide (complex 2) by proton elimination reaction. Another PAY is added to complex 2 forming complex 3, of which the terminal H is transferred intramolecularly. Followed by Csp—Csp coupling and ligand exchange reactions, 1,4-diphenyl-1,3-butadiyne (DPBY) is obtained. Besides, the complex 3 could also become DPBY via subsequent intermolecular proton elimination, Csp—Csp coupling, SET and ligand exchange reactions. In addition, under the strong base condition, phenylacetylene anion (PAY) is generated and then add to complex 2 forming complex 3'. Complex 3' then changes into complex 14 through disproportionation reaction, where the singlet-triplet coupling is involved. Complex 14 is dissociated into DPBY directly. The charges are computed for all the involved complexes, which are Cu(0)/(I) intermediates and Cu(II)/(I) transition states, illustrating the observed copper species with different valence in experiments.

Key words: Cu-catalysis with variable valence, homo-coupling of terminal alkyne, single electron transfer, redox potential, density functional theory