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Published on: May 26, 2019
A [5 + 1] annulation strategy for the synthesis of multifunctional biaryls and p-teraryls from 1,6-Michael acceptor
Shally1, Ismail Althagafi2, Ranjay Shaw1
1Department of Chemistry, University of Delhi, North Campus, Delhi-110007, India. rpratap@chemistry.du.ac.in ramendrapratap@gmail.com.
Abstract:
A new type of ketene dithioacetal, 2-(3,3-bis-methylsulfanyl-1-arylallylidene)malononitriles containing 1,4 and 1,6-Michael acceptors, were synthesized to study their reactivity for the synthesis of a new molecular entity. We report a [5 + 1] annulation strategy for the construction of multifunctional biaryls and p-teraryls by the selection of a suitable nucleophilic source. The reaction of p-nitrotoluene with 2-(3,3-bis-methylsulfanyl-1-aryl-allylidene)malononitriles under basic conditions produces p-teraryls in good yields, while the use of nitroethane as the nucleophile source provides functionalized biaryls through cyclization, followed by denitration. This reaction requires mild conditions and exhibits good functional group tolerance.
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