TY - JOUR
T1 - Discriminating halogen-bonding from other noncovalent interactions by a combined NOE NMR/DFT approach
AU - Ciancaleoni, Gianluca
AU - Bertani, Roberta
AU - Rocchigiani, Luca
AU - Sgarbossa, Paolo
AU - Zuccaccia, Cristiano
AU - Macchioni, Alceo
PY - 2015/1/2
Y1 - 2015/1/2
N2 - Herein a combined NOE NMR/DFT methodology to discriminate between adducts held together by halogen bonding (XB) and other noncovalent interactions (non‐XB, such as lone pair/π), based on the determination of the XB donors′ and acceptors′ relative orientation, is proposed. In particular, 19F,1H HOESY NMR spectroscopy experiments and DFT calculations on different XB donors, such as perfluorohexyl iodide (I1), iodopentafluorobenzene (I2) and bromopentafluorobenzene (Br), combined with different Lewis bases, such as 1,4‐diazabicyclo[2.2.2]octane (DABCO) and 2,4,6‐trimethylpyridine (Me3Py), were performed. The results clearly show that in the case DABCO/I1 the XB adduct is practically the only one present in solution, whereas for the other pairs a certain amount of non‐XB adduct is present. Combining DFT and HOESY results, the amount of non‐XB adducts can be roughly quantified under our experimental conditions as 4 % for DABCO/I2, between 10 and 20 % for Me3Py/I1 and Me3Py/I2, and 44 % for DABCO/Br.
AB - Herein a combined NOE NMR/DFT methodology to discriminate between adducts held together by halogen bonding (XB) and other noncovalent interactions (non‐XB, such as lone pair/π), based on the determination of the XB donors′ and acceptors′ relative orientation, is proposed. In particular, 19F,1H HOESY NMR spectroscopy experiments and DFT calculations on different XB donors, such as perfluorohexyl iodide (I1), iodopentafluorobenzene (I2) and bromopentafluorobenzene (Br), combined with different Lewis bases, such as 1,4‐diazabicyclo[2.2.2]octane (DABCO) and 2,4,6‐trimethylpyridine (Me3Py), were performed. The results clearly show that in the case DABCO/I1 the XB adduct is practically the only one present in solution, whereas for the other pairs a certain amount of non‐XB adduct is present. Combining DFT and HOESY results, the amount of non‐XB adducts can be roughly quantified under our experimental conditions as 4 % for DABCO/I2, between 10 and 20 % for Me3Py/I1 and Me3Py/I2, and 44 % for DABCO/Br.
UR - https://www.scopus.com/pages/publications/84920488080
U2 - 10.1002/chem.201404883
DO - 10.1002/chem.201404883
M3 - Article
SN - 0947-6539
VL - 21
SP - 440
EP - 447
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 1
ER -