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Synthesis 2010(2): 208-210  
DOI: 10.1055/s-0029-1217127
SHORTPAPER
© Georg Thieme Verlag Stuttgart ˙ New York

p-Quinols and p-Quinol Ethers from 2,4,6-Trialkylphenols

Kanji Omura*,
College of Nutrition, Koshien University, Momijigaoka, Takarazuka, Hyogo 665-0006, Japan
Fax: +81(72)7668732; e-Mail: k.omura@iris.eonet.ne.jp;
Further Information

Publication History

Received 24 August 2009
Publication Date:
20 November 2009 (online)

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Abstract

The oxidation of 2,4,6-trialkylphenols with lead(IV) oxide and 70% perchloric acid in water-acetone or in alcohols gives p-quinols or p-quinol ethers, respectively. Some nonmetallic oxidants serve the same purpose.

Key words

oxidations - 2,4,6-trialkylphenols - p-quinols - p-quinol ethers - lead(IV) oxide - perchloric acid - nonmetallic oxidants

    References

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1

Current address: 4-5-2, Matsuodai, Inagawa, Hyogo 666-0261, Japan.

8

More recently, an N-F reagent has been shown to slowly oxidize 1 (except 1b) in MeCN-protic solvent (H2O, MeOH, and primary alcohols) mixtures affording the p-quinols and p-quinol ethers. An attempt to prepare 2an, 2ao, or 2cn by the use of the reagent was not made in this laboratory. See ref. 2b.

10

The mechanism of the NaIO3/70% HClO4 oxidation awaits further investigation.

11

The reaction involves a bromination-debromination mechanism. Details will be discussed in a subsequent paper.

13

The reaction would involve an iodination-deiodination mechanism. See ref. 12c.

16

¹H NMR (90 MHz, CDCl3): δ = 0.92 (s, 9 H), 1.09 (d, J = 6.2 Hz, 6 H), 1.24 (s, 18 H), 3.40 (sept, J = 6.2 Hz, 1 H), 6.59 (s, 2 H). The ¹H NMR spectrum of 2cn in CCl4 has been reported. See ref. 9.

17

For purification and identification of the product, see ref. 4.