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. 2018 Aug 17;83(16):9522-9529.
doi: 10.1021/acs.joc.8b01249. Epub 2018 Jun 27.

Synthesis of Azolo[1,3,5]triazines via Rhodium(III)-Catalyzed Annulation of N-Azolo Imines and Dioxazolones

Gia L Hoang  1 , Kim Søholm Halskov  1 , Jonathan A Ellman  1
Affiliations

Synthesis of Azolo[1,3,5]triazines via Rhodium(III)-Catalyzed Annulation of N-Azolo Imines and Dioxazolones

Gia L Hoang et al. J Org Chem. .

Abstract

A wide range of azolo[1,3,5]triazines were obtained by Rh(III)-catalyzed annulation of N-azolo imines and dioxazolones. The reaction proceeds by the first catalytic C-H amidation of an imidoyl C-H bond followed by cyclodehydration. Good yields were obtained for N-azolo imines derived from aminoazoles and aromatic and heteroaromatic aldehydes. A range of dioxazolone amidating reagents were employed to introduce aryl, heteroaryl, and alkyl substituents. The reaction was also performed with a benchtop setup at 1 mmol scale using microwave heating.

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Conflict of interest statement

The authors declare no competing financial interest

Figures

Scheme 1.
Scheme 1.
Preparation of Bridgehead N-Fused [5,6]-Bicyclic Heterocycles via Catalytic C-H Functionalization
Scheme 2.
Scheme 2.
Dioxazolone Scope for Rh(III)-Catalyzed Annulation to Give Azolotriazines 6a
Scheme 3.
Scheme 3.
N-Azolo Imine Scope for Rh(III)-Catalyzed Annulations to Give Azolotriazines 6a
Scheme 3.
Scheme 3.
N-Azolo Imine Scope for Rh(III)-Catalyzed Annulations to Give Azolotriazines 6a
Scheme 4.
Scheme 4.
Bench-top Reaction Set Up on 1 mmol Scale
Scheme 5.
Scheme 5.
Proposed Mechanism for Annulation
See this image and copyright information in PMC

References

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