Abstract
Iron- and manganese-catalyzed para-selective oxidative amination of (4-R)phenols by primary and secondary anilines was developed. Depending on the identity of the R group, the products of this efficient reaction are either benzoquinone anils (C–N coupling) that are produced via a sequential oxidative amination/dehydrogenation (R = H), oxidative amination/elimination (R = OMe) steps, or N,O-biaryl compounds (C–C coupling) that are formed when R = alkyl through an oxidative amination/[3,3]-sigmatropic rearrangement (quinamine rearrangement) process.
Highlights
Oxidative cross-coupling reactions[1] between phenols and anilines are powerful methods for assembling Ncontaining phenolic compounds that are applied in a variety of applications, such as natural product synthesis and asymmetric catalysis.[2]
We examined alternative redox systems for mediating the oxidative cross-coupling between phenols and primary anilines
Oxidative Coupling between Phenols and Tertiary Anilines (A), Secondary Anilines (B), and Primary and Secondary Anilines (C, This Work)
Summary
Oxidative cross-coupling reactions[1] between phenols and anilines are powerful methods for assembling Ncontaining phenolic compounds that are applied in a variety of applications, such as natural product synthesis and asymmetric catalysis.[2]. The coupling between 2,6-dimethoxyphenol (1a, 1.5 equiv) and 3,4-dimethoxyaniline (2a, 1 equiv) was chosen as a model reaction; we commenced by examining catalytic conditions based on meso-tetraphenylporphyrin iron(III) chloride complex [Fe[TPP]Cl (1 mol %), t-BuOOH (2 equiv), HFIP, rt] that were developed in our group for the oxidative crosscoupling of phenols.[16] Under these conditions, benzoquinone anil 3 was obtained in 78% yield (entry 3).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
