Organic Letters
Letter
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Scheme 6. One-Pot Diaryl Ether Synthesis from Epoxide
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oxidation level of the functionalized products via the addition of
simple, inexpensive additives. We have also developed a
catalytic isomerization of 2-aryloxy-1-arylethanols and a tele-
scoped synthesis of diaryl ethers directly from commodity
epoxide starting materials. Ongoing studies are focused on
further applications of hydrogen transfer in catalysis, and these
results will be reported in due course.
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studies.
(9) For examples of diaryl ether motifs in biologically relevant
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ASSOCIATED CONTENT
* Supporting Information
■
S
The Supporting Information is available free of charge on the
Optimization data, experimental procedures, character-
ization of new compounds and spectral data (PDF)
AUTHOR INFORMATION
■
Corresponding Author
ORCID
(11) Employing alkyl alcohols (e.g., benzyl alcohol or 1-decanol) as
the nucleophile under optimized reaction conditions (or with NaH or
KOt-Bu as base) results in the formation of complex mixtures of
products. Employing thiophenol as the nucleophile results in catalyst
deactivation, with starting materials returned.
(12) For selected reviews on the importance of aryl amines in the
preparation of agrochemicals, dyes, and pharmaceuticals, see:
(a) Weissermel, K.; Arpe, H. Industrial Organic Chemistry; Wiley-
VCH: Weinheim, 1997. (b) Lawrence, S. A. Amines: Synthesis,
Properties and Application; Cambridge University Press: Cambridge,
UK, 2004. (c) Vitaku, E.; Smith, D. T.; Njardarson, J. T. J. Med. Chem.
2014, 57, 10257−10274.
(13) The modest isolated yield obtained when using diethylamine as
the nucleophile is attributed to its low boiling point (bp = 56 °C)
Dalton, J. S.; Snyder, J. J. J. Am. Chem. Soc. 1975, 97, 5192−5194.
(14) No products arising from N-alkyation were observed when
amines were employed as the nucleophile.
Notes
The authors declare no competing financial interest.
Information about the data that underpins the results presented
in this article, including how to access them, can be found in
ACKNOWLEDGMENTS
■
We gratefully acknowledge the School of Chemistry, Cardiff
University, for generous support, the EPSRC-funded Bath/
Bristol/Cardiff Catalysis Centre for Doctoral Training (K.P.,
EP/L016443/1), the EPSRC Doctoral Training Grant for a
part-funded Ph.D. studentship (B.G.R-B., EP/M507842/1),
and the EPSRC UK National Mass Spectrometry Facility at
Swansea University.
(15) Chlorinated arenes, 1-(4-chlorophenyl)ethan-1-ol and 1-(2-
chlorophenyl)ethan-1-ol, undergo dehydrogenation; however, the
corresponding ketones do not participate in SNAr with phenol under
these reaction conditions.
(16) (a) Trost, B. M. Angew. Chem., Int. Ed. Engl. 1995, 34, 259−281.
(b) Trost, B. M. Acc. Chem. Res. 2002, 35, 695−705.
(17) Nichols, J. M.; Bishop, L. M.; Bergman, R. G.; Ellman, J. A. J.
Am. Chem. Soc. 2010, 132, 12554−12555.
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