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An Expedient Method for the Umpolung Coupling of Enols with Heteronucleophiles **
Author(s) -
GarcíaVázquez Víctor,
Carretero Cerdán Alba,
SanzMarco Amparo,
GómezBengoa Enrique,
MartínMatute Belén
Publication year - 2022
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.202201000
Subject(s) - umpolung , nucleophile , chemistry , enol , silylation , heteroatom , combinatorial chemistry , electrophile , reactivity (psychology) , organic chemistry , primary (astronomy) , halogen , allylic rearrangement , alkyl , catalysis , medicine , alternative medicine , physics , pathology , astronomy
In this paper, we present an unprecedented and general umpolung protocol that allows the functionalization of silyl enol ethers and of 1,3‐dicarbonyl compounds with a large range of heteroatom nucleophiles, including carboxylic acids, alcohols, primary and secondary amines, azide, thiols, and also anionic carbamates derived from CO 2 . The scope of the reaction also extends to carbon‐based nucleophiles. The reaction relies on the use of 1‐bromo‐3,3‐dimethyl‐1,3‐dihydro‐1λ 3 [ d ][1,2]iodaoxole, which provides a key α‐brominated carbonyl intermediate. The reaction mechanism has been studied experimentally and by DFT, and we propose formation of an unusual enolonium intermediate with a halogen‐bonded bromide.