Strong N−X⋅⋅⋅O−N Halogen Bonds: A Comprehensive Study on N‐Halosaccharin Pyridine N ‐Oxide Complexes
In: Angewandte Chemie International Edition, Jg. 58 (2019-11-07), S. 18610-18618
Online
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Zugriff:
A study of the strong N-X⋅⋅⋅- O-N+ (X=I, Br) halogen bonding interactions reports 2×27 donor×acceptor complexes of N-halosaccharins and pyridine N-oxides (PyNO). DFT calculations were used to investigate the X⋅⋅⋅O halogen bond (XB) interaction energies in 54 complexes. A simplified computationally fast electrostatic model was developed for predicting the X⋅⋅⋅O XBs. The XB interaction energies vary from -47.5 to -120.3 kJ mol-1 ; the strongest N-I⋅⋅⋅- O-N+ XBs approaching those of 3-center-4-electron [N-I-N]+ halogen-bonded systems (ca. 160 kJ mol-1 ). 1 H NMR association constants (KXB ) determined in CDCl3 and [D6 ]acetone vary from 2.0×100 to >108 m-1 and correlate well with the calculated donor×acceptor complexation enthalpies found between -38.4 and -77.5 kJ mol-1 . In X-ray crystal structures, the N-iodosaccharin-PyNO complexes manifest short interaction ratios (RXB ) between 0.65-0.67 for the N-I⋅⋅⋅- O-N+ halogen bond.
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Strong N−X⋅⋅⋅O−N Halogen Bonds: A Comprehensive Study on N‐Halosaccharin Pyridine N ‐Oxide Complexes
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Autor/in / Beteiligte Person: | J. Mikko Rautiainen ; Rissanen, Kari ; Puttreddy, Rakesh ; Mäkelä, Toni |
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Zeitschrift: | Angewandte Chemie International Edition, Jg. 58 (2019-11-07), S. 18610-18618 |
Veröffentlichung: | Wiley, 2019 |
Medientyp: | unknown |
ISSN: | 1521-3773 (print) ; 1433-7851 (print) |
DOI: | 10.1002/anie.201909759 |
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