Web Table 1. Free energy profile of the uncatalysed model π2s+π4s cycloaddition reaction

<p>Web Table 1. Free energy profile of the uncatalysed model π2s+π4s cycloaddition reaction</p

Web Table 1. Free energy profile of the uncatalysed model cycloaddition reaction

<p>Two complementary catalytic systems are reported for the 1,3-dipolar cycloaddition of azides and iodoalkynes. These are based on two commercially available/readily available copper complexes, [CuCl(IPr)] or [CuI(PPh3)3], which are active at low metal loadings and in the absence of any other additive (IPr system). These systems were used for the first reported mechanistic studies on this particular reaction. An experimental/computational-DFT approach allowed to establish that 1) some iodoalkynes might be prone to dehalogenation under copper catalysis conditions and, more importantly, 2) that two distinct mechanistic pathways are likely to be competitive with these catalysts; through a copper(III) metallacycle or via direct p-activation of the starting alkyne.</p

Web Table 2. Free energy profile of the formation of iodotriazoles via a Cu(III) metallacycle pathway

<p>Two complementary catalytic systems are reported for the 1,3-dipolar cycloaddition of azides and iodoalkynes. These are based on two commercially available/readily available copper complexes, [CuCl(IPr)] or [CuI(PPh3)3], which are active at low metal loadings and in the absence of any other additive (IPr system). These systems were used for the first reported mechanistic studies on this particular reaction. An experimental/computational-DFT approach allowed to establish that 1) some iodoalkynes might be prone to dehalogenation under copper catalysis conditions and, more importantly, 2) that two distinct mechanistic pathways are likely to be competitive with these catalysts; through a copper(III) metallacycle or via direct p-activation of the starting alkyne.</p

Web Table 2. Free energy profile of the formation of iodotriazoles via a Cu(III) metallacycle pathway

<p>Web Table 2. Free energy profile of the formation of iodotriazoles via a Cu(III) metallacycle pathway</p

Catalytic and Computational Studies of N‑Heterocyclic Carbene or Phosphine-Containing Copper(I) Complexes for the Synthesis of 5‑Iodo-1,2,3-Triazoles

Two complementary catalytic systems are reported for the 1,3-dipolar cycloaddition of azides and iodoalkynes. These are based on two commercially available/readily available copper complexes, [CuCl­(IPr)] or [CuI­(PPh₃)₃], which are active at low metal loadings (PPh₃ system) or in the absence of any other additive (IPr system). These systems were used for the first reported mechanistic studies on this particular reaction. An experimental/computational-DFT approach allowed to establish that (1) some iodoalkynes might be prone to dehalogenation under copper catalysis conditions and, more importantly, (2) two distinct mechanistic pathways are likely to be competitive with these catalysts, either through a copper­(III) metallacycle or via direct π-activation of the starting iodoalkyne

Functionalized Organocuprates: Structures of Lithium and Magnesium Grignard 2-Methoxyphenylcuprates

Lithium and magnesium Grignard diorganocuprates incorporating the functionalized aryl group 2-methoxyphenyl have been prepared and structurally characterized in the solid state. [Cu₄Li₂(C₆H₄OMe-2)₆(THF)₂] (<b>2</b>) and [Cu­(C₆H₄OCH₃-2)₂Mg­(THF)₂X] (<b>3-X</b>; X = Cl, Br) all exhibit coordination of the s-block metal center by the methoxy oxygen, resulting in the formation of novel aggregates and favoring contact ion pair structures. In contrast, separate ion pair structures had previously been observed under similar conditions for nonfunctionalized arylcuprates. The magnesium organocuprates <b>3-Cl</b> and <b>3-Br</b> are of particular interest, being rare examples of structurally characterized Grignard-derived organocuprates and the first examples of functionalized Grignard organocuprates. All reported organocuprates undergo oxidative aryl coupling in the presence of O₂ or PhNO₂ to give 2,2′-dimethoxybiphenyl

Functionalized Organocuprates: Structures of Lithium and Magnesium Grignard 2-Methoxyphenylcuprates

Lithium and magnesium Grignard diorganocuprates incorporating the functionalized aryl group 2-methoxyphenyl have been prepared and structurally characterized in the solid state. [Cu₄Li₂(C₆H₄OMe-2)₆(THF)₂] (<b>2</b>) and [Cu­(C₆H₄OCH₃-2)₂Mg­(THF)₂X] (<b>3-X</b>; X = Cl, Br) all exhibit coordination of the s-block metal center by the methoxy oxygen, resulting in the formation of novel aggregates and favoring contact ion pair structures. In contrast, separate ion pair structures had previously been observed under similar conditions for nonfunctionalized arylcuprates. The magnesium organocuprates <b>3-Cl</b> and <b>3-Br</b> are of particular interest, being rare examples of structurally characterized Grignard-derived organocuprates and the first examples of functionalized Grignard organocuprates. All reported organocuprates undergo oxidative aryl coupling in the presence of O₂ or PhNO₂ to give 2,2′-dimethoxybiphenyl