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Abstract Bond breaking and forming are essential components of chemical reactions. Recently, the structure and formation of covalent bonds in single molecules have been studied by non-contact atomic force microscopy (AFM). Here, we report the details of a single dative bond breaking process using non-contact AFM. The dative bond between carbon monoxide and ferrous phthalocyanine was ruptured via mechanical forces applied by atomic force microscope tips; the process was quantitatively measured and characterized both experimentally and via quantum-based simulations. Our results show that the bond can be ruptured either by applying an attractive force of ~150 pN or by a repulsive force of ~220 pN with a significant contribution of shear forces, accompanied by changes of the spin state of the system. Our combined experimental and computational studies provide a deeper understanding of the chemical bond breaking process.
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Organocatalysis by a multidentate halogen-bond donor: an alternative to hydrogen-bond based catalysis
A charge neutral iodoethynyl-based multidentate halogen-bond donor was synthesized and successfully utilized as an organocatalyst in a benchmark Ritter-type solvolysis reaction. The catalytic activity was monitored using 1 H NMR spectroscopy and several control experiments were systematically carried out in order to rule out hidden catalysis based on other functional groups.
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- Award ID(s):
- 1826982
- PAR ID:
- 10284634
- Date Published:
- Journal Name:
- New Journal of Chemistry
- Volume:
- 43
- Issue:
- 21
- ISSN:
- 1144-0546
- Page Range / eLocation ID:
- 8311 to 8314
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9nj01404g
