Efficient homocoupling reactions of halide compounds catalyzed by manganese (II) chloride

Abstract

A new efficient homocoupling reaction was reported in one pot by a combination of metallic magnesium and a catalytic amount of manganese (II) chloride. Various aromatic and alkyl halides underwent homocoupling smoothly, affording the corresponding symmetrical homocoupling compounds in moderate to good yields. The readily available MnCl 2 , the mild reaction conditions and the operational simplicity and practicability allow for an easy and practical procedure for the purpose of carbon-carbon bond formation.

Ligand‐Free Iron‐Catalyzed Homo‐Coupling of Aryllithium Reagents

“…13 C NMR (126 MHz, CDCl 3 ) δ=141.6, 139.3, 133.8, 126.5, ‐1.1 ppm. Data was in accordance with that reported in the literature [18] …”

“…[7b,17] 4,4'-Bis(trimethylsilyl)-1,1'-biphenyl (2 m). [18] Prepared according to General Procedure 2. Purified by preparative thin-layer chromatography using hexane.…”

Ligand‐Free Iron‐Catalyzed Homo‐Coupling of Aryllithium Reagents

“…13 C NMR (126 MHz, CDCl 3 ) δ=141.6, 139.3, 133.8, 126.5, ‐1.1 ppm. Data was in accordance with that reported in the literature [18] …”

“…[7b,17] 4,4'-Bis(trimethylsilyl)-1,1'-biphenyl (2 m). [18] Prepared according to General Procedure 2. Purified by preparative thin-layer chromatography using hexane.…”

N-Heterocyclic Carbene Ligand-Controlled Chemodivergent Suzuki–Miyaura Cross Coupling

“…1 H NMR (500 MHz, CDCl 3 , δ): 7.48 (d, J = 8.4 Hz, 4H), 7.40 (d, J = 8.4 Hz, 4H); 13 C­{ 1 H} NMR (125 MHz, CDCl 3 , δ): 138.6, 133.9, 129.2, 128.4. Spectral data are consistent with those previously reported …”

Homocoupling Reaction of Aryl Halides Catalyzed by Metal Cations in Isostructural Coordination Polymers

“…According to frontier orbital theory, the frontier orbitals have the most important influence on the catalytic performance. − The highest occupied molecular orbital (HOMO) is primarily to provide electrons, and the lowest unoccupied molecular orbital (LUMO) is the electron acceptor. , The smaller the LUMO energy, the more drop in energy after accepting electrons leading to a more stable system. − In the homocoupling of aryl halides catalyzed by coordination polymers, Lewis acid catalysts act as electrophiles, and the lower energy of LUMO of coordination polymers is beneficial to promote the reaction. As shown in Table , the energy of LUMO of 1 – 4 is negative, and 4 < 3 < 2 < 1 .…”

Ligand‐Free Iron‐Catalyzed Homo‐Coupling of Aryllithium Reagents

“…13 C NMR (126 MHz, CDCl 3 ) δ=141.6, 139.3, 133.8, 126.5, ‐1.1 ppm. Data was in accordance with that reported in the literature [18] …”

“…[7b,17] 4,4'-Bis(trimethylsilyl)-1,1'-biphenyl (2 m). [18] Prepared according to General Procedure 2. Purified by preparative thin-layer chromatography using hexane.…”

N-Heterocyclic Carbene Ligand-Controlled Chemodivergent Suzuki–Miyaura Cross Coupling

“…1 H NMR (500 MHz, CDCl 3 , δ): 7.48 (d, J = 8.4 Hz, 4H), 7.40 (d, J = 8.4 Hz, 4H); 13 C­{ 1 H} NMR (125 MHz, CDCl 3 , δ): 138.6, 133.9, 129.2, 128.4. Spectral data are consistent with those previously reported …”

Homocoupling Reaction of Aryl Halides Catalyzed by Metal Cations in Isostructural Coordination Polymers

“…According to frontier orbital theory, the frontier orbitals have the most important influence on the catalytic performance. − The highest occupied molecular orbital (HOMO) is primarily to provide electrons, and the lowest unoccupied molecular orbital (LUMO) is the electron acceptor. , The smaller the LUMO energy, the more drop in energy after accepting electrons leading to a more stable system. − In the homocoupling of aryl halides catalyzed by coordination polymers, Lewis acid catalysts act as electrophiles, and the lower energy of LUMO of coordination polymers is beneficial to promote the reaction. As shown in Table , the energy of LUMO of 1 – 4 is negative, and 4 < 3 < 2 < 1 .…”

Ligand‐Free Iron‐Catalyzed Homo‐Coupling of Aryllithium Reagents

“…13 C NMR (126 MHz, CDCl 3 ) δ=141.6, 139.3, 133.8, 126.5, ‐1.1 ppm. Data was in accordance with that reported in the literature [18] …”

“…[7b,17] 4,4'-Bis(trimethylsilyl)-1,1'-biphenyl (2 m). [18] Prepared according to General Procedure 2. Purified by preparative thin-layer chromatography using hexane.…”

N-Heterocyclic Carbene Ligand-Controlled Chemodivergent Suzuki–Miyaura Cross Coupling

“…1 H NMR (500 MHz, CDCl 3 , δ): 7.48 (d, J = 8.4 Hz, 4H), 7.40 (d, J = 8.4 Hz, 4H); 13 C­{ 1 H} NMR (125 MHz, CDCl 3 , δ): 138.6, 133.9, 129.2, 128.4. Spectral data are consistent with those previously reported …”

Homocoupling Reaction of Aryl Halides Catalyzed by Metal Cations in Isostructural Coordination Polymers

“…According to frontier orbital theory, the frontier orbitals have the most important influence on the catalytic performance. − The highest occupied molecular orbital (HOMO) is primarily to provide electrons, and the lowest unoccupied molecular orbital (LUMO) is the electron acceptor. , The smaller the LUMO energy, the more drop in energy after accepting electrons leading to a more stable system. − In the homocoupling of aryl halides catalyzed by coordination polymers, Lewis acid catalysts act as electrophiles, and the lower energy of LUMO of coordination polymers is beneficial to promote the reaction. As shown in Table , the energy of LUMO of 1 – 4 is negative, and 4 < 3 < 2 < 1 .…”