Abstract
The reaction of Ni(ClO4)2 with 4 equiv of pyrazole (pzH) in MeCN leads to [Ni(pzH)2(HN= C(Me)pz)2](ClO4) 2 via the intermediate [Ni(MeCN)2(pzH)4] (ClO4)2, which is the first pyrazole-nitrile coupling reaction activated by a Ni(II) complex. The reaction is also successfully conducted with other nitries RCN bearing an electron-donating group (R = Et, Bz) and is counteranion-specific. The reaction proceeds more quickly with NO 3̄ as counteranion than with ClO4̄, and BF4̄ is found to be unsatisfactory for the coupling reaction. As for the X-ray crystal structures, [Ni(MeCN) 2(pzH)4](ClO4)2 possesses stronger pyrazolyl NH... anion hydrogen-bonding interactions than does [Ni(MeCN) 2(pzH)4](BF4)2. The same trend is also observed by solution IR (pyrazolyl NH) analysis. The supramolecular structure of the complex [Ni(pzH)2(HN=C(Me)pz)2](ClO 4)2 displays a two-dimensional network dominated by cooperative face-toface π-π stacking and edge-to-face CH...π bonding interactions. In addition, a mechanism based on anion-mediated/hydrogen-bonding- driven proton transfer for the coupling reaction is proposed.
| Original language | English |
|---|---|
| Pages (from-to) | 4923-4928 |
| Number of pages | 6 |
| Journal | Organometallics |
| Volume | 28 |
| Issue number | 17 |
| DOIs | |
| Publication status | Published - 2009 Sep 14 |
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All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
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Effects of the counteranion on the pyrazole-nitrile coupling reaction mediated by nickel(II) ions. / Hsieh, Chang Chih; Lee, Chia Jung; Horng, Yih Chern.
In: Organometallics, Vol. 28, No. 17, 14.09.2009, p. 4923-4928.Research output: Contribution to journal › Article
TY - JOUR
T1 - Effects of the counteranion on the pyrazole-nitrile coupling reaction mediated by nickel(II) ions
AU - Hsieh, Chang Chih
AU - Lee, Chia Jung
AU - Horng, Yih Chern
PY - 2009/9/14
Y1 - 2009/9/14
N2 - The reaction of Ni(ClO4)2 with 4 equiv of pyrazole (pzH) in MeCN leads to [Ni(pzH)2(HN= C(Me)pz)2](ClO4) 2 via the intermediate [Ni(MeCN)2(pzH)4] (ClO4)2, which is the first pyrazole-nitrile coupling reaction activated by a Ni(II) complex. The reaction is also successfully conducted with other nitries RCN bearing an electron-donating group (R = Et, Bz) and is counteranion-specific. The reaction proceeds more quickly with NO 3̄ as counteranion than with ClO4̄, and BF4̄ is found to be unsatisfactory for the coupling reaction. As for the X-ray crystal structures, [Ni(MeCN) 2(pzH)4](ClO4)2 possesses stronger pyrazolyl NH... anion hydrogen-bonding interactions than does [Ni(MeCN) 2(pzH)4](BF4)2. The same trend is also observed by solution IR (pyrazolyl NH) analysis. The supramolecular structure of the complex [Ni(pzH)2(HN=C(Me)pz)2](ClO 4)2 displays a two-dimensional network dominated by cooperative face-toface π-π stacking and edge-to-face CH...π bonding interactions. In addition, a mechanism based on anion-mediated/hydrogen-bonding- driven proton transfer for the coupling reaction is proposed.
AB - The reaction of Ni(ClO4)2 with 4 equiv of pyrazole (pzH) in MeCN leads to [Ni(pzH)2(HN= C(Me)pz)2](ClO4) 2 via the intermediate [Ni(MeCN)2(pzH)4] (ClO4)2, which is the first pyrazole-nitrile coupling reaction activated by a Ni(II) complex. The reaction is also successfully conducted with other nitries RCN bearing an electron-donating group (R = Et, Bz) and is counteranion-specific. The reaction proceeds more quickly with NO 3̄ as counteranion than with ClO4̄, and BF4̄ is found to be unsatisfactory for the coupling reaction. As for the X-ray crystal structures, [Ni(MeCN) 2(pzH)4](ClO4)2 possesses stronger pyrazolyl NH... anion hydrogen-bonding interactions than does [Ni(MeCN) 2(pzH)4](BF4)2. The same trend is also observed by solution IR (pyrazolyl NH) analysis. The supramolecular structure of the complex [Ni(pzH)2(HN=C(Me)pz)2](ClO 4)2 displays a two-dimensional network dominated by cooperative face-toface π-π stacking and edge-to-face CH...π bonding interactions. In addition, a mechanism based on anion-mediated/hydrogen-bonding- driven proton transfer for the coupling reaction is proposed.
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U2 - 10.1021/om9004753
DO - 10.1021/om9004753
M3 - Article
AN - SCOPUS:69949179558
VL - 28
SP - 4923
EP - 4928
JO - Organometallics
JF - Organometallics
SN - 0276-7333
IS - 17
ER -