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The halogen bond with isocyano carbon reduces isocyanide odor.

ABSTRACT: Predominantly, carbon atoms of various species function as acceptors of noncovalent interactions when they are part of a π-system. Here, we report on the discovery of a halogen bond involving the isocyano carbon lone pair. The co-crystallization or mechanochemical liquid-assisted grinding of model mesityl isocyanide with four iodoperfluorobenezenes leads to a series of halogen-bonded adducts with isocyanides. The obtained adducts were characterized by single-crystal and powder X-ray diffraction, solid-state IR and ¹³C NMR spectroscopies, and also by thermogravimetric analysis. The formation of the halogen bond with the isocyano group leads to a strong reduction of the isocyanide odor (3- to 46-fold gas phase concentration decrease). This manipulation makes isocyanides more suitable for laboratory storage and usage while preserving their reactivity, which is found to be similar between the adducts and the parent isocyanide in some common transformations, such as ligation to metal centers and the multi-component Ugi reaction.

SUBMITTER: Mikherdov AS

PROVIDER: S-EPMC7286913 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Integrating carbon-halogen bond formation into medicinal plant metabolism.

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Carbon-Halogen Bond Activation by Selenium-Based Chalcogen Bonding.

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Activation of a Metal-Halogen Bond by Halogen Bonding.

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Halogen Bond Asymmetry in Solution.

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| S-EPMC6209183 | biostudies-literature

Aromatization modulates the activity of small organic molecules as promoters for carbon-halogen bond activation.

Project description:The combination of small organic molecules and a base serves as a unique system for the activation carbon-halogen bonds in haloarenes by single electron transfer (SET). However, most of the molecules employed as promoters only allow for the activation of aryl iodides, and efficient activation of aryl bromides and chlorides under this mode is still rather challenging. Herein, we report the discovery of a structurally simple yet powerful promoter molecule, indoline, which exhibits unusually high activity in promoting the activation of haloarenes by SET. In the presence of t-BuOK and a trace amount of oxygen, indoline promotes the formation of aryl radicals not only from aryl iodides and bromides, but also from unactivated aryl chlorides (e.g., chlorobenzene) under relatively mild conditions. Mechanistic studies reveal the molecular basis for its high activity, for which the aromatization process plays a key role in modulating the electron transfer process.

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Halogen-Bond Assisted Photoinduced Electron Transfer.

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| S-EPMC6149982 | biostudies-literature

Evidence for halogen bond covalency in acyclic and interlocked halogen-bonding receptor anion recognition.

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