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Hexafluoroisopropanol mediated benign synthesis of 2H-pyrido[1,2-a]pyrimidin-2-ones by using a domino protocol.

ABSTRACT: Domino strategy has been used for the synthesis of 2H-pyrido[1,2-a]pyrimidin-2-ones. Four sequential reactions: aza-Michael addition, water elimination, intramolecular acyl substitution, and [1,3]-H shift were observed in this domino protocol. Hexafluoroisopropanol is used as a promotor and recyclable solvent in this cascade process. Availability of inexpensive 2-aminopyridines and wide variety of Michael acceptors such as commercially available acrylates and unactivated Baylis-Hillman adducts makes this methodology a huge reservoir of novel fused N-heterocycles as bioactive and potential therapeutic agents. The reaction mechanism has been proposed and rationalized by density functional theory calculation. Products are obtained up to 95% yield.

SUBMITTER: Alsharif Z

PROVIDER: S-EPMC5800427 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Hexafluoroisopropanol mediated benign synthesis of 2H-pyrido[1,2-a]pyrimidin-2-ones by using a domino protocol.

Alsharif Zakeyah Z Ali Mohamad Akbar MA Alkhattabi Hessa H Jones Derika D Delancey Evan E Ravikumar P C PC Alam Mohammad A MA

New journal of chemistry = Nouveau journal de chimie 20171020 24

Domino strategy has been used for the synthesis of 2H-pyrido[1,2-a]pyrimidin-2-ones. Four sequential reactions: aza-Michael addition, water elimination, intramolecular acyl substitution, and [1,3]-H shift were observed in this domino protocol. Hexafluoroisopropanol is used as a promotor and recyclable solvent in this cascade process. Availability of inexpensive 2-aminopyridines and wide variety of Michael acceptors such as commercially available acrylates and unactivated Baylis-Hillman adducts m ...[more]

PMID: 29430169

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