TY - JOUR
T1 - Solvent-dependent reactivity and photochemistry of dinuclear and mononuclear platinum (IV) azido triazaolato complexes
AU - Yao, Kezi
AU - Bertran, Arnau
AU - Morgan, Jacques
AU - Greenhalgh, Charlotte
AU - Edkins, Katharina
AU - Bowen, Alice
AU - Farrer, Nicola J.
N1 - Funding Information:
This work was supported by the Wellcome Trust (201406/Z/16/Z), Cancer Research UK (CR-UK) grant number C5255/A18085, through the Cancer Research UK Oxford Centre and the John Fell Fund. NF thanks Dr. Alan Kenwright and Profs. Stephen Faulkner and Andrew Weller for helpful discussions. EPR measurements were performed in the Centre for Advanced Electron Spin Resonance at the University of Oxford supported by the EPSRC (EP/L011972/1). A.M.B. gratefully acknowledges her fellowship support from the Royal Society and EPSRC for a Dorothy Hodgkin Fellowship (DH160004), and A.M.B and A.B acknowledge the support from the Royal Society Grant for Research Fellows (RGF\R1\180099).
Publisher Copyright:
© 2021 The Authors. European Journal of Inorganic Chemistry published by Wiley-VCH GmbH
PY - 2021/4/15
Y1 - 2021/4/15
N2 - Reaction between the platinum(IV) azido complex trans,trans,trans-[Pt(py)2(N3)2(OH)2] (1) and 1,4-diphenyl-2-butyne-1,4-dione 2 in MeCN produces the intermediate peroxide-bridged dimeric platinum(IV) azido triazolato species (5), which has been characterised by X-ray crystallography. However, if the reaction between 1 and 2 is conducted in MeOH it results in decomposition. Over time in MeCN, dimer (5) converts into mononuclear complexes trans,trans,trans-[Pt(py)2(N3)(triazole)(OH)2] (3 a/3 b), which are in dynamic exchange. If resuspended in protic solvents (MeOH,H2O), 3 a/3 b undergo a slow (22 d) irreversible rearrangement to a cyclised platinum(IV) species 4 which contains a formally N,O-chelated ligand. Conversion of 3 a/3 b to 4 in d4-MeOH can be accelerated (384x) by irradiation with visible light, although continued irradiation also produces N3. and OH. radicals, and the [4-N3]+ species can be readily detected by ESI-MS. Solvent choice significantly effects both the cycloaddition reaction between 1 and 2, and the stability of the resultant complexes.
AB - Reaction between the platinum(IV) azido complex trans,trans,trans-[Pt(py)2(N3)2(OH)2] (1) and 1,4-diphenyl-2-butyne-1,4-dione 2 in MeCN produces the intermediate peroxide-bridged dimeric platinum(IV) azido triazolato species (5), which has been characterised by X-ray crystallography. However, if the reaction between 1 and 2 is conducted in MeOH it results in decomposition. Over time in MeCN, dimer (5) converts into mononuclear complexes trans,trans,trans-[Pt(py)2(N3)(triazole)(OH)2] (3 a/3 b), which are in dynamic exchange. If resuspended in protic solvents (MeOH,H2O), 3 a/3 b undergo a slow (22 d) irreversible rearrangement to a cyclised platinum(IV) species 4 which contains a formally N,O-chelated ligand. Conversion of 3 a/3 b to 4 in d4-MeOH can be accelerated (384x) by irradiation with visible light, although continued irradiation also produces N3. and OH. radicals, and the [4-N3]+ species can be readily detected by ESI-MS. Solvent choice significantly effects both the cycloaddition reaction between 1 and 2, and the stability of the resultant complexes.
KW - Azides
KW - Photoactivity
KW - Platinum
KW - Radicals
KW - Structure elucidation
U2 - 10.1002/ejic.202100041
DO - 10.1002/ejic.202100041
M3 - Article
C2 - 34248415
SN - 1434-1948
VL - 2021
SP - 1397
EP - 1404
JO - European Journal of Inorganic Chemistry
JF - European Journal of Inorganic Chemistry
IS - 14
ER -