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Fe(OTf)3-catalysed Friedel-Crafts reaction of benzenoid arenes with ?,?-unsaturated carbonyl compounds: easy access to 1,1-diarylalkanes.

ABSTRACT: A simple and efficient method for the synthesis of 1,1-diarylalkanes via the Friedel-Crafts-type alkylation reaction of electron-rich arenes with cinnamic acid ester derivatives or chalcones is reported. Iron triflate has been found to be the best catalyst for the Friedel-Crafts-type alkylation reaction with ?,?-unsaturated carbonyl compounds. This reaction afforded ?,?-diaryl carbonyl compounds in good yields (65-93%) and with excellent regioselectivities. Remarkably, this method is also compatible with a variety of indoles to provide 3-indolyl-aryl carbonyl compounds in excellent yields. Great efforts have been made to deduce a plausible reaction mechanism based on isotopic labelling experiments.

SUBMITTER: Bhattacharya A

PROVIDER: S-EPMC5666261 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Fe(OTf)3-catalysed Friedel-Crafts reaction of benzenoid arenes with α,β-unsaturated carbonyl compounds: easy access to 1,1-diarylalkanes.

Bhattacharya Aditya A Shukla Pushpendra Mani PM Maji Biswajit B

Royal Society open science 20171025 10

A simple and efficient method for the synthesis of 1,1-diarylalkanes via the Friedel-Crafts-type alkylation reaction of electron-rich arenes with cinnamic acid ester derivatives or chalcones is reported. Iron triflate has been found to be the best catalyst for the Friedel-Crafts-type alkylation reaction with α,β-unsaturated carbonyl compounds. This reaction afforded β,β-diaryl carbonyl compounds in good yields (65-93%) and with excellent regioselectivities. Remarkably, this method is also compat ...[more]

PMID: 29134078

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