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H-bonded reusable template assisted para-selective ketonisation using soft electrophilic vinyl ethers.

ABSTRACT: In nature, enzymatic pathways generate C_aryl-C(O) bonds in a site-selective fashion. Synthetically, C_aryl-C(O) bonds are synthesised in organometallic reactions using prefunctionalized substrate materials. Electrophilic routes are largely limited to electron-rich systems, non-polar medium, and multiple product formations with a limited scope of general application. Herein we disclose a directed para-selective ketonisation technique of arenes, overriding electronic bias and structural congestion, in the presence of a polar protic solvent. The concept of hard-soft interaction along with in situ activation techniques is utilised to suppress the competitive routes. Mechanistic pathways are investigated both experimentally and computationally to establish the hypothesis. Synthetic utility of the protocol is highlighted in formal synthesis of drugs, drug cores, and bioactive molecules.

SUBMITTER: Maji A

PROVIDER: S-EPMC6123475 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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H-bonded reusable template assisted para-selective ketonisation using soft electrophilic vinyl ethers.

Maji Arun A Dahiya Amit A Lu Gang G Bhattacharya Trisha T Brochetta Massimo M Zanoni Giuseppe G Liu Peng P Maiti Debabrata D

Nature communications 20180904 1

In nature, enzymatic pathways generate Caryl-C(O) bonds in a site-selective fashion. Synthetically, Caryl-C(O) bonds are synthesised in organometallic reactions using prefunctionalized substrate materials. Electrophilic routes are largely limited to electron-rich systems, non-polar medium, and multiple product formations with a limited scope of general application. Herein we disclose a directed para-selective ketonisation technique of arenes, overriding electronic bias and ...[more]

PMID: 30181575

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