Open Access Repository
Disclosure of some obscure mechanistic aspects of the copper-catalyzed click reactions involving N2 elimination promoted by the use of electron-deficient azides from a DFT perspective


Full text not available from this repository.
Abstract
We have used density functional theory to explore the copper(I)-catalyzed reaction between a mesyl azide and a terminal alkyne that leads to a ketenimine whose interaction with nucleophilic water produces an amide. It is well reported in the literature that a cuprated triazole intermediate is formed during the course of such a catalytic cycle. In this contribution, we investigated the stability of this key intermediate by varying the R substituent on the azide and found that electron-withdrawing R substituents make this intermediate more reactive toward ring opening/N2 elimination; an electron-withdrawing R substituent facilitates this process by weakening the N–N bond being cleaved. We also rationalized why the cycloaddition step in this class of click reactions is required to proceed via a binuclear mechanism. The copper(I) acetylide intermediate formed during the catalysis gains extra stability upon scavenging a second Cu complex, resulting in the cycloaddition step occurring with a lower activation barrier. We also noticed that, similar to the ring closure step, inclusion of a second Cu complex may accelerate the ring opening/N2 elimination process. It was shown that the ketenimine needs to coordinate to a copper center via its nitrogen atom in order to be activated toward hydrolysis.
Item Type: | Article |
---|---|
Authors/Creators: | Roohzadeh, R and Nasiri, B and Chipman, A and Yates, BF and Ariafard, A |
Keywords: | density functional theory, activation energy, click reactions, electron-deficient azides |
Journal or Publication Title: | Organometallics |
Publisher: | Amer Chemical Soc |
ISSN: | 0276-7333 |
DOI / ID Number: | 10.1021/acs.organomet.8b00691 |
Copyright Information: | © 2018 American Chemical Society |
Related URLs: | |
Item Statistics: | View statistics for this item |
Actions (login required)
![]() |
Item Control Page |