Next Article in Journal
Metabolism of Tanshinone IIA, Cryptotanshinone and Tanshinone I from Radix Salvia Miltiorrhiza in Zebrafish
Previous Article in Journal
Effect of β-Carotene on Immunity Function and Tumour Growth in Hepatocellular Carcinoma Rats
Previous Article in Special Issue
Hypervalent Nonbonded Interactions of a Divalent Sulfur Atom. Implications in Protein Architecture and the Functions
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Communication

IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone®

by
Muhammet Uyanik
1,
Tatsuya Mutsuga
1 and
Kazuaki Ishihara
1,2,*
1
Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan
2
Japan Science and Technology Agency (JST), CREST, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan
*
Author to whom correspondence should be addressed.
Molecules 2012, 17(7), 8604-8616; https://doi.org/10.3390/molecules17078604
Submission received: 25 June 2012 / Revised: 6 July 2012 / Accepted: 12 July 2012 / Published: 18 July 2012
(This article belongs to the Special Issue Hypervalent Compounds)

Abstract

:
We have developed the first example of hypervalent iodine(V)-catalyzed regioselective oxidation of phenols to o-quinones. Various phenols could be oxidized to the corresponding o-quinones in good to excellent yields using catalytic amounts of sodium salts of 2-iodobenzenesulfonic acids (pre-IBSes) and stoichiometric amounts of Oxone® as a co-oxidant under mild conditions. The reaction rate of IBS-catalyzed oxidation under nonaqueous conditions was further accelerated in the presence of an inorganic base such as potassium carbonate (K2CO3), a phase transfer catalyst such as tetrabutylammonium hydrogen sulfate (nBu4NHSO4), and a dehydrating agent such as anhydrous sodium sulfate (Na2SO4).

Graphical Abstract

1. Introduction

o-Quinones are useful synthetic intermediates for the synthesis of medicinally and biologically important compounds [1,2,3,4,5,6,7,8,9,10,11]. To date, numerous methods have been reported for the preparation of p-quinones by the oxidation of phenols or their derivatives [12,13,14]. For instance, the oxidation of phenols with Fremy’s radical [15], MeReO3 [16], dimethyldioxirane [17], or benzeneseleninic anhydride [18] mostly gives p-quinones, unless blocked by a substituent. However, there have been only a few studies on the direct conversion of a phenol into an o-quinone. In 2002, Pettus and colleagues reported the regioselective oxidation of phenols with stoichiometric amounts of 2-iodoxybenzoic acid (IBX) to the o-quinones [19]. After Pettus’ pioneering findings, this method was applied to the synthesis of biologically active compounds such as catecholestrogen [20], catecholamine [21], hydroxytyrosol [22], and flavonoid [23] derivatives. In 2010, Harvey and colleagues reported the regiospecific oxidation of polycyclic aromatic phenols to quinones using hypervalent iodine(III and V) reagents [24]. Accordingly, oxidation with IBX in non-aqueous DMF gives o-quinones, while oxidation with bis(trifluoro-acetoxy)iodobenzene in aqueous DMF gives p-quinones selectively.
The hypervalent organoiodine(III or V)-catalyzed oxidation reactions with co-oxidants have also been extensively investigated over the past seven years [25,26,27,28,29]. From 2007 to 2009, Yakura and colleagues reported that p-alkoxyphenols or p-arylphenols were oxidized to the corresponding p-quinones or p-quinols, respectively, in excellent yields using catalytic amounts of 4-iodophenoxyacetic acid with Oxone® (2KHSO5•KHSO4•K2SO4) as a co-oxidant in aqueous acetonitrile [30,31,32]. To the best of our knowledge, however, there are no successful examples of a catalytic hypervalent iodine system for the regio-selective oxidation of phenols to o-quinones.
We recently reported a highly efficient and chemoselective oxidation of various alcohols to carbonyl compounds such as aldehydes, carboxylic acids, and ketones with powdered Oxone® in the presence of catalytic amounts (1–5 mol%) of 2-iodobenzenesulfonic acids (pre-IBSes) or their sodium salts (1a–c) under nonaqueous conditions (Scheme 1a) [33,34,35,36]. 2-Iodoxybenzenesulfonic acids (IBSes) 2a–c as iodine(V), which are generated in situ from 1a–c and Oxone®, serve as the actual catalysts for the oxidations (Scheme 1b) [33,34,35,36]. According to previous theoretical calculations [33], the relatively ionic character of the intramolecular hypervalent iodine-OSO2 bond of IBS 2a lowers the twisting barrier of the alkoxyperiodinane intermediate. In fact, 2a shows much more catalytic activity than IBX [33]. The oxidation rate in 2a-catalyzed oxidation under nonaqueous conditions is further accelerated by the use of powdered Oxone® due to its increased surface area. When Oxone® is used under nonaqueous conditions, Oxone® wastes can be removed by simple filtration. Furthermore, we developed the oxidative rearrangement of tertiary allylic alcohols to β-disubstituted α,β-unsaturated ketones with Oxone® catalyzed by in situ-generated 5-Me-IBS (2b) (Scheme 1c) [37]. The addition of inorganic bases such as K2CO3, and a phase transfer catalyst such as tetrabutylammonium hydrogen sulfate (nBu4NHSO4), extended the substrate scope for oxidative rearrangement reactions. Recently, the IBS/Oxone® catalytic oxidation system was applied to benzylic oxidation [38] and oxidation of fluorinated alcohols [39]. As part of our continuing interest in the IBS-catalyzed oxidation system, we report here the in situ-generated IBS-catalyzed regioselective oxidation of phenols to o-quinones with Oxone®.
Scheme 1. In situ generated IBS (2)-catalyzed selective oxidation of alcohols and oxidative rearrangement of tertiary allylic alcohols with powdered Oxone® under non-aqueous conditions.
Scheme 1. In situ generated IBS (2)-catalyzed selective oxidation of alcohols and oxidative rearrangement of tertiary allylic alcohols with powdered Oxone® under non-aqueous conditions.
Molecules 17 08604 g001

2. Results and Discussion

Initially, we investigated the reactivity and regioselectivity of the oxidation of 1-naphthol (3a) using conventional hypervalent catalysts under non-aqueous conditions (Table 1). A mixture of 3a, powdered Oxone® (2 equiv.) and nBu4NHSO4 (10 mol%) as a solid-liquid phase transfer catalyst was heated in ethyl acetate at 40 °C in the presence of 5 mol% of iodobenzene or Yakura’s pre-catalyst (4-iodophenoxyacetic acid, 6) [30,31,32] (entries 2 and 3). However only trace amounts of the desired products were detected, and more than 80% of 3a was recovered with small amounts of unidentified side-products. The reaction was somewhat messy, and more than 80% of 3a was recovered. Additionally, the use of pre-IBX (7) gave both 1,2-naphthoquinone (4a) and 1,4-naphthoquinone (5a) each in 5% yield, and 80% of 3a was recovered (entry 4). In sharp contrast, and to our delight, when pre-IBS (1a) was used, 3a was completely consumed in 11 h, and quinones 4a and 5a were obtained in respective yields of 64% and 5% together with highly polar compounds (entry 5). As expected from our previous works [33,37], the use of pre-5-Me-IBS (1b) or pre-4,5-Me2-IBS (1c) gave slightly better results, and the former gave the best results (entries 6 and 7). Interestingly, when the oxidation was conducted in aqueous acetonitrile, 5a was obtained selectively as a major product in 51% yield (entry 8). We found that the carbon(1)-carbon(2) bond of o-quinone 4a was oxidatively cleaved under identical aqueous conditions to highly polar compounds including trans-2-carboxycinnamic acid (8) [40] and other minor unidentified compounds (Scheme 2). These results indicated that non-aqueous conditions were essential for the preparation of o-quinones in high yields. According to our previous works, the selective oxidation of acid-sensitive alcohols could be achieved in the presence of anhydrous sodium sulfate as a dehydrating agent [33,37]. Additionally, the oxidation rate and selectivity could be further accelerated with the use of additional base to buffer the acidity of the reaction mixture [37]. Based on these previous findings, the reaction of 3a was carried out in the presence of 1 equiv. of potassium carbonate and anhydrous sodium sulfate under the modified conditions in entry 6. Thus, 4a was obtained in 78% yield after 1 h, when Oxone® and K2CO3 were sufficiently premixed in the presence of anhydrous Na2SO4 in ethyl acetate at room temperature for 24 h before the addition of 2b, 3a, and nBu4NHSO4 (entry 9). Notably, the use of nBu4NHSO4 was essential for the present oxidation, since almost no reaction occurred in its absence (entry 10).
Table 1. Hypervalent iodine-catalyzed oxidation of 1-naphthol 3a. Molecules 17 08604 i001
Table 1. Hypervalent iodine-catalyzed oxidation of 1-naphthol 3a. Molecules 17 08604 i001
EntryPre-cat.Additive (equiv.)Time (h)4a, Yield (%) a5a, Yield (%) a
124trace btrace b
2PhI24trace btrace b
36 f24trace btrace b
47 g245 b5 b
51a11645
61b8696
71c9676
8 c1b3.5trace b51
9 d1bK2CO3 (1)1786
10 e1bK2CO3 (1)24trace btrace b
a Isolated yield; b 1H-NMR analysis; c The reaction was performed in CH3CN-H2O (2:1, v/v) instead of EtOAc; d After a mixture of Oxone® and K2CO3 in ethyl acetate was vigorously stirred in the presence of Na2SO4 for 24 h at room temperature, 1a, 3a and nBu4NHSO4 were added; e In the absence of nBu4NHSO4; f 6: 4-Iodophenoxyacetic acid; g7: 2-Iodobenzoic acid.
Scheme 2. Oxidative carbon-carbon bond cleavage of 4a to dicarboxylic acid 8 under aqueous conditions.
Scheme 2. Oxidative carbon-carbon bond cleavage of 4a to dicarboxylic acid 8 under aqueous conditions.
Molecules 17 08604 g002
To explore the generality of the in situ-generated 5-Me-IBS-catalyzed oxidation of phenols with Oxone®, various naphthols, phenanthrols, and phenols 3b–l were examined as substrates under the optimized conditions: powdered Oxone® (2 equiv.) and potassium carbonate (1 equiv.) in ethyl acetate were vigorously stirred at room temperature for 24 h in the presence of anhydrous sodium sulfate, and then 1b (5 mol%), 3a and nBu4NHSO4 (10 mol%) were added and the resulting mixture was heated to 40 °C (Table 2). As expected, 4a was obtained in slightly better yield by the oxidation of 2-naphthol 3b than by the oxidation of 3a (Table 2, entry 1 versus Table 1, entry 9). 4-Bromo- or chloro-substituted 1-naphthols 3c and 3d gave the corresponding o-quinones in high yields (entries 2 and 3). Notably, the desired 1,2-quinones were obtained as a major product under our catalytic conditions even with the oxidation of 4-methoxy-1-naphthol (3e) and 4-methoxyphenol (3j) (entries 4 and 9). Accordingly, the previous iodine(III)-mediated oxidation of para-alkoxy phenols gave 1,4-quinones exclusively [30,31,32]. Additionally, the oxidation of phenanthrols 3g and 3h gave the desired 1,2-quinones in excellent yields (entries 6 and 7). These polycyclic aromatic quinones were obtained in only moderate yields by stoichiometric oxidations with IBX [24]. The oxidation of 2,4-di-tert-butylphenol (3k) gave desired o-quinone 4k in 73% yield after 24 h (entry 10). In contrast, the oxidation of 3-methoxy-1-naphthol (3l) gave 1,4-quinone 5l rather than 1,2-quinone 4l as a major product (Scheme 3). Additionally, the oxidation of 3l with Oxone® even in the absence of 1b also gave 5l selectively, but in lower yield (63%) after 6 h.
Table 2. 5-Me-IBS-catalyzed oxidation of naphthols, phenanthrols and phenols 3 a. Molecules 17 08604 i002
Table 2. 5-Me-IBS-catalyzed oxidation of naphthols, phenanthrols and phenols 3 a. Molecules 17 08604 i002
Entry34Time (h)Yield (%) b
1 Molecules 17 08604 i0034a484
3b
Molecules 17 08604 i004 Molecules 17 08604 i005
23c (R = Cl)4c580
33d (R = Br)4d375
43e (R = OMe)4e250 c
5 Molecules 17 08604 i0064a272
3f
6 Molecules 17 08604 i007 Molecules 17 08604 i008290
3g4g
7 Molecules 17 08604 i009 Molecules 17 08604 i010297
3h4h
8 Molecules 17 08604 i011 Molecules 17 08604 i012563
3i4i
9 Molecules 17 08604 i013 Molecules 17 08604 i014566 d
3j4j
10 Molecules 17 08604 i015 Molecules 17 08604 i0162473
3k4k
a Reaction conditions: 3 (1 mmol), powdered Oxone® (2 mmol), K2CO3 (1 mmol), 1b (0.05 mmol), nBu4NHSO4 (0.1 mmol), Na2SO4 (1 g), EtOAc (10 mL), 40 °C. Oxone® and K2CO3 were pre-treated in EtOAc for 24 h at room temperature in the presence of anhydrous Na2SO4; b Isolated yield; c 1,4-Naphthoquinone (5a) was obtained in 15% yield; d 2-tert-Butyl-1,4-quinone 5j obtained in 16% yield.
Scheme 3. Oxidation of 3-methoxy-1-naphthol 3i.
Scheme 3. Oxidation of 3-methoxy-1-naphthol 3i.
Molecules 17 08604 g003
Based on previous studies [24,33,34,35,36,37], a proposed reaction mechanism is depicted in Scheme 4. In situ-generated IBS (2) reversibly combines with 3 to give IBS-phenol complex 10, which serves to transfer oxygen from an iodoxy group (IV = O) to the ortho-site of the phenol through concerted intramolecular [2,3]-rearrangement. During this process, the iodine(V) atom is concurrently reduced to the iodine(III)-catechol complex 11, which gives o-quinones 4 and pre-IBS 1. The catalytic cycle of IBS 2 can be accomplished by the regeneration of 2 through the successive oxidations of 1 and 9 with tetrabutylammonium peroxymonosulfate, nBu4NHSO5, which can be generated in situ from KHSO5 and nBu4NHSO4.
Scheme 4. Possible mechanism for the IBS-catalyzed oxidation of phenols.
Scheme 4. Possible mechanism for the IBS-catalyzed oxidation of phenols.
Molecules 17 08604 g004
While, the reason for the para-selective oxidation of 3l is not yet clear, a plausible mechanism is depicted in Scheme 5. The peroxo-IBS complex 12 might be generated reversibly in situ from IBS and ammonium Oxone®. Electrophilic aromatic oxidation at the highly nucleophilic carbon(4) position of 3l with 12 gives 13, which easily tautomerizes to IBS-hydroquinone complex 14. Finally, the oxidation of hydroquinone gives 1,4-quinone 5l and iodine(III) 9. Notably, 5l was also obtained by the oxidation of 3l with only Oxone® (Scheme 3) [41]. The reactivity of Oxone® should be accelerated by complexation with IBS [42]. Thus, the oxidation was faster and the chemical yield of 5l was higher in the presence of IBS (Scheme 3).
Scheme 5. Possible mechanism for the para-selective oxidation of 3l.
Scheme 5. Possible mechanism for the para-selective oxidation of 3l.
Molecules 17 08604 g005

3. Experimental

3.1. General

Infrared (IR) spectra were recorded on a Jasco FT/IR 460 plus spectrometer. 1H-NMR spectra (400 MHz) and 13C-NMR spectra (100 MHz) were measured on a Jeol ECS-400 spectrometer at ambient temperature. Data were recorded as follows: chemical shift in ppm from internal tetramethylsilane on the δ scale, multiplicity (s = singlet; d = doublet; t = triplet; q = quartet; m = multiplet), coupling constant (Hz), integration, and assignment. Chemical shifts were recorded in ppm from the resonance of the solvent used as the internal standard (deuterochloroform at 77.0 ppm). For thin-layer chromatography (TLC) analysis throughout this work, Merck precoated TLC plates (silica gel 60 GF254 0.25 mm) were used. The products were purified by column chromatography on silica gel (E. Merck Art. 9385). High-resolution mass spectral analysis (HRMS) and elemental analysis were performed at the Chemical Instrument Center, Nagoya University. Pre-catalysts 1ac were prepared according to known procedures [33]. Additionally, 1a and 1b (as potassium salts) are also commercially available from Junsei Chemical Japan, TCI and Sigma-Aldrich. Starting materials 3d [43], 3f [44], 3g [24], and 3l [45] were prepared according to known procedures. In experiments that required solvents, ethyl acetate, acetonitrile, and nitromethane were purchased from Wako Pure Chemical Industries, Ltd. in “anhydrous” form and used without any purification. Other simple chemicals were analytical-grade and obtained commercially.

3.2. General Procedure for the Oxidation Phenol to Quinone

A mixture of powdered Oxone® (1.2 g, 2.0 mmol), potassium carbonate (0.14 g, 1.0 mmol) and anhydrous sodium sulfate (1.0 g, dried by a heat-gun under vacuum before use), in ethyl acetate (4.0 mL) was vigorously stirred at room temperature for 24 h. To the resulting mixture were added 3 (1.0 mmol), nBu4NHSO4 (34 mg, 0.10 mmol), 1b (17 mg, 0.050 mmol), and EtOAc (6.0 mL), and the resulting mixture was stirred vigorously at 40 °C. The reaction was monitored by TLC analysis. After the reaction was completed, the reaction mixture was cooled to room temperature and the solids were filtered-off and washed with EtOAc. The filtrate was washed with water, and the aqueous layers were extracted with EtOAc. The combined organic layers were washed by water and brine, and dried over anhydrous Na2SO4. The solvents were removed under vacuo, and the residue was purified by column chromatography on silica gel (hexane-EtOAc as eluent) to give the corresponding quinones 4 or 5.
1,2-Naphthoquinone (4a) [46]. Brown solid; TLC, Rf = 0.21 (hexane–EtOAc = 4:1); 1H-NMR (CDCl3) δ 6.45 (d, J = 10 Hz, 1H), 7.25 (d, J = 8.2 Hz, 1H), 7.45 (d, J = 7.8 Hz, 1H), 7.53 (dd, J = 6.4, 7.8 Hz, 1H), 7.66 (ddd, J = 1.4, 5.9, 6.4 Hz, 1H), 8.13 (d, J = 7.3 Hz, 1H); 13C-NMR (CDCl3) δ 128.0, 130.0, 130.3, 131.0, 131.7, 134.9, 136.0, 145.6, 179.0, 181.0.
1,4-Naphthoquinone (5a) [47]. Yellow solid; TLC, Rf = 0.41 (hexane–EtOAc = 4:1); 1H-NMR (CDCl3) δ 6.99 (s, 1H), 7.77 (m, 2H), 8.10 (m, 2H); 13C-NMR (CDCl3) δ 126.6, 132.0, 134.1, 138.8, 185.2.
trans-2-Carboxycinnamic acid (8) [40]. Pale yellow solid; 1H-NMR (DMSO-d6) δ 6.43 (d, J = 16 Hz, 1H), 7.51 (t, J = 7.5 Hz, 1H), 7.60 (t, J = 6.8 Hz, 1H), 7.82 (d, J = 7.3 Hz, 1H), 7.88 (dd, J = 0.9, 7.8 Hz, 1H), 8.31 (d, J = 16 Hz, 1H), 13C-NMR (DMSO-d6) δ 121.4, 127.8, 129.8, 130.4, 131.1, 132.2, 134.9, 142.6, 167.5, 168.2.
4-Chloro-1,2-naphthoquinone (4c). Brown solid; TLC, Rf = 0.58 (hexane–EtOAc = 1:1); IR (KBr) 1,658, 1,582, 1,322, 1,287, 1,242, 936, 769 cm−1; 1H-NMR (CDCl3) δ 6.76 (s, 1H), 7.63 (t, J = 7.8 Hz, 1H), 7.77 (t, J = 7.8 Hz, 1H), 7.90 (d, J = 7.8 Hz, 1H), 8.17 (d, J = 7.8 Hz, 1H); 13C-NMR (CDCl3) δ 127.7, 128.0, 130.2, 130.6, 132.2, 132.7, 135.9, 152.8, 178.1, 178.4; HRMS (FAB+) m/z calcd for C11H14O3 (M+H) 193.0056, found 193.0054.
4-Bromo-1,2-naphthoquinone (4d) [48]. Brown solid; TLC, Rf = 0.62 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 7.05 (s, 1H), 7.61 (t, J = 7.5 Hz, 1H), 7.77 (t, J = 7.3 Hz, 1H), 7.90 (d, J = 7.8 Hz, 1H), 8.15 (d, J = 7.3 Hz, 1H); 13C-NMR (CDCl3) δ 130.1, 130.6, 130.9, 132.1, 133.6, 136.0, 145.9, 178.2.
4-Methoxy-1,2-naphthoquinone (4e) [49]. Yellow solid; TLC, Rf = 029 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 4.08 (s, 3H), 5.99 (s, 1H), 7.59 (dd, J = 7.3, 7.8 Hz, 1H), 7.71 (t, J = 7.8 Hz, 1H), 7.87 (d, J = 8.2 Hz, 1H), 8.13 (d, J = 7.3 Hz, 1H); 13C-NMR (CDCl3) δ 57.0, 103.2, 124.9, 129.2, 130.4, 131.7, 132.1, 135.1, 168.8, 179.5, 179.6.
1,2-Phenanthraquinone (4g) [24]. Red solid; TLC, Rf = 0.54 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 6.59 (d, J = 10 Hz, 2H), 7.70 (m, 2H), 7.91 (m, 1H), 7.98 (d, J = 8.2 Hz, 1H), 8.17 (d, J = 8.2 Hz, 1H), 8.31 (m, 2H); 13C-NMR (CDCl3) δ 123.6, 124.4, 127.7, 128.6, 129.4, 129.7, 129.8, 131.4, 132.0, 137.3, 139.6, 179.5, 180.8.
9,10-Phenanthraquinone (4h) [50]. Yellow solid; TLC, Rf = 0.50 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 7.47 (dd, J = 7.3, 7.8 Hz, 2H), 7.72 (ddd, J = 1.4, 6.9, 7.3 Hz, 2H), 8.03 (d, J = 8.3 Hz, 2H), 8.20 (dd, J = 1.4, 6.4 Hz, 2H); 13C-NMR (CDCl3) δ 124.1, 129.7, 130.5, 131.0, 135.9, 136.2, 180.3.
4-tert-Butyl-1,2-benzoquinone (4i) [51]. Brown solid; TLC, Rf = 0.38 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 1.24 (s, 9H), 6.29 (d, J = 2.2 Hz, 1H), 6.40 (d, J = 10 Hz, 1H), 7.19 (dd, J = 2.5, 10 Hz, 1H); 13C-NMR (DMSO-d6) δ 27.4, 35.3, 123.2, 129.4, 140.2 161.5, 180.0.
3-tert-Butyl-5-methoxy-1,2-benzoquinone (4j). Red solid; TLC, Rf = 0.42 (hexane–EtOAc = 1:1); IR (KBr) 1,649, 1,630, 1,589, 1,440, 1,367, 1,228, 1,007, 900, 783; 1H-NMR (CDCl3) δ 1.26 (s, 9H), 3.84 (s, 3H), 5.73 (d, J = 2.7 Hz, 1H), 6.62 (d, J = 3.2 Hz, 1H); 13C-NMR (CDCl3) δ 28.9, 35.2 56.7, 101.0, 133.0, 151.5, 170.0, 178.6, 179.9; HRMS (FAB+) m/z calcd for C11H14O3 (M+H) 195.1021, found 195.1013.
2-tert-Butyl-1,4-benzoquinone (5j) [52]. Brown solid; TLC, Rf = 0.71 (hexane–EtOAc = 4:1); 1H-NMR (CDCl3, 400 MHz) δ 1.30 (s, 9H), 6.61 (d, J = 1.4 Hz, 1H), 6.69 (d, J = 1.4 Hz, 2H); 13C-NMR (CDCl3, 100 MHz) δ 29.2, 35.3, 131.6, 135.0, 138.7, 156.1, 188.5.
3,5-Di-tert-Butyl-1,2-benzoquinone (4k) [52]. Brown solid; TLC, Rf = 0.71 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 1.23 (s, 9H), 1.27 (s, 9H), 6.22 (d, J = 2.3 Hz, 1H), 6.93 (d, J = 2.3 Hz, 1H); 13C-NMR (CDCl3) δ 28.0, 29.3, 35.6, 36.1, 122.2, 133.6, 150.0, 163.4, 180.2, 181.2.
3-Methoxy-1,4-naphthoquinone (5l) [53]. Yellow solid; TLC, Rf = 0.46 (hexane–EtOAc = 1:1); 1H-NMR (CDCl3) δ 3.90 (s, 3H), 6.17 (s, 1H); 13C-NMR (CDCl3) δ 56.6, 110.0, 126.3, 126.8, 131.1, 132.1, 133.4, 134.5, 160.5, 180.2, 185.0.

4. Conclusions

We have demonstrated the in situ-generated IBS-catalyzed regioselective oxidation of phenols to o-quinones with Oxone®. The reaction rate is accelerated with the use of inorganic bases such as K2CO3, a phase transfer catalyst such as tetrabutylammonium hydrogen sulfate (nBu4NHSO4), and dehydrating agent such as Na2SO4. Various phenols are oxidized to the corresponding o-quinones in good to excellent yields. To the best of our knowledge, this is the first example of the hypervalent iodine-catalyzed oxidation of phenols to o-quinones.

Acknowledgments

Financial support for this project was provided in part by JSPS.KAKENHI (24245020, 22750087). T.M. thanks “the Nagoya University IGER Program in Green Natural Sciences for Leading Graduate Schools from MEXT” for a research fellowship.

References

  1. Quideau, S.; Pouységu, L. Synthetic uses of orthoquinonemonoketals and their orthoquinols variants. A review. Org. Prep. Proced. Int. 1999, 31, 617–680. [Google Scholar] [CrossRef]
  2. Scott, J.D.; Williams, R.M. Chemistry and biology of the tetrahydroisoquinoline antitumor antibiotics. Chem. Rev. 2002, 102, 1669–1730. [Google Scholar]
  3. Magdziak, D.; Meek, S.J.; Pettus, T.R.R. Cyclohexadienoneketals and quinols: Four building blocks potentially useful for enantioselective synthesis. Chem. Rev. 2004, 104, 1383–1430. [Google Scholar]
  4. Pouységu, L.; Deffieux, D.; Quideau, S. Hypervalent iodine-mediated phenol dearomatization in natural product synthesis. Tetrahedron 2010, 66, 2235–2261. [Google Scholar]
  5. Danishefsky, S.J.; Mazza, S.; McCurry, P. Diels-Alder reactions of o-benzoquinones. J. Org. Chem. 1974, 39, 3610–3611. [Google Scholar]
  6. Omote, Y.; Tomotake, A.; Kashima, C. Reaction of 1,2-benzoquinones with enamines. J. Chem. Soc. Perkin Trans. 1 1988, 2, 151–156. [Google Scholar]
  7. Nair, V.; Maliakal, D.; Treesa, P.M.; Rath, N.P.; Eigendorf, G.K. [4+2] Cycloaddition reactions of o-benzoquinones with styrenes: A facile synthesis of bicyclo[2.2.2]octenediones. Synthesis 2000, 850–856. [Google Scholar]
  8. Stavber, S.; Zupan, M. The effect of heteroatoms on the reactions of organic molecules with cesium fluoroxysulphate. Tetrahedron 1992, 48, 5875–5882. [Google Scholar] [CrossRef]
  9. Osman, F.H.; Abd El-Rahman, N.M.; El-Samahy, F.A. Reaction of phosphonium ylides with 4-triphenylmethyl-1,2-benzoquinone. Tetrahedron 1993, 49, 8691–8704. [Google Scholar]
  10. Viallon, L.; Reinaud, O.; Capdevielle, P.; Maumy, M. Synthesis of new 4-alkylamino-5-methoxy-2H-pyran-2-ones. Tetrahedron Lett. 1995, 36, 6669–6672. [Google Scholar]
  11. Takuwa, A.; Kai, R.; Kawasaki, K.I.; Nishigaichi, Y.; Iwamoto, H. New formal [3+2] photoaddition of vinyl ethers to o-benzoquinones. J. Chem. Soc. Chem. Commun. 1996, 703–704. [Google Scholar]
  12. Dudfield, P.J. Synthesis of quinones. In Comprehensive Organic Synthesis; Trost, B.M., Flemming, I., Eds.; Pergamon Press: Oxford, UK, 1991; Volume 7, pp. 345–356. [Google Scholar]
  13. Gallagher, P.T. The synthesis of quinones. Contemp. Org. Synth. 1996, 3, 433–446. [Google Scholar]
  14. Akai, S.; Kita, Y. Review of recent progress in the synthesis of p-quinones and p-dihydroquinones through oxidation of phenol derivatives. Org. Prep. Proced. Int. 1998, 30, 603–629. [Google Scholar]
  15. Deya, P.M.; Dopico, M.; Raso, A.G.; Morey, J.; Saa, J.M. On the regioselectivity of the Fremy’s salt oxidation of phenols. Tetrahedron 1987, 43, 3523–3532. [Google Scholar]
  16. Saladino, R.; Neri, V.; Mincione, E.; Marini, S.; Coletta, M.; Fiorucci, C.; Filippone, P. A new and efficient synthesis of ortho- and para-benzoquinones of cardanol derivatives by the catalytic system MeReO3-H2O2. J. Chem. Soc. Perkin Trans. 1 2000, 4, 581–586. [Google Scholar]
  17. Crandall, J.K.; Zucco, M.; Kirsch, R.S.; Coppert, D.M. The formation of orthoquinones in the dimethyldioxirane oxidation of phenols. Tetrahedron Lett. 1991, 32, 5441–5444. [Google Scholar]
  18. Barton, D.H.R.; Finet, J.P.; Thomas, M. Comparative oxidation of phenols with benzeneseleninic anhydride and with benzeneseleninic acid. Tetrahedron 1988, 44, 6397–6406. [Google Scholar]
  19. Magdziak, D.; Rodriguez, A.A.; van de Water, R.W.; Pettus, T.R.R. Regioselective oxidation of phenols to o-quinones with o-iodoxybenzoic acid (IBX). Org. Lett. 2002, 4, 285–288. [Google Scholar]
  20. Pezzella, A.; Lista, L.; Napolitano, A.; d’Ischia, M. An expedient one-pot entry to catecholestrogens and other catechol compounds via IBX-mediated phenolic oxygenation. Tetrahedron Lett. 2005, 46, 3541–3544. [Google Scholar]
  21. Bernini, R.; Crisante, F.; Barontini, M.; Fabrizi, G. A new and efficient route for the synthesis of naturally occurring catecholamines. Synthesis 2009, 2009, 3838–3842. [Google Scholar]
  22. Bernini, R.; Mincione, E.; Crisante, F.; Barontini, M.; Fabrizi, G. A novel use of the recyclable polymer-supported IBX: An efficient chemoselective and regioselective oxidation of phenolic compounds. The case of hydroxytyrosol derivatives. Tetrahedron Lett. 2009, 50, 1307–1310. [Google Scholar]
  23. Barontini, M.; Bernini, R.; Crisante, F.; Fabrizi, G. Selective and efficient oxidative modifications of flavonoids with 2-iodoxybenzoic acid (IBX). Tetrahedron 2010, 66, 6047–6053. [Google Scholar]
  24. Wu, A.; Duan, Y.; Xu, D.; Penning, T.M.; Harvey, R.G. Regiospecific oxidation of polycyclic aromatic phenols to quinones by hypervalent iodine reagents. Tetrahedron 2010, 66, 2111–2118. [Google Scholar]
  25. Richardson, R.D.; Wirth, T. Hypervalent iodine goes catalytic. Angew. Chem. Int. Ed. Engl. 2006, 45, 4402–4404. [Google Scholar] [CrossRef]
  26. Zhdankin, V.V.; Stang, P.J. Chemistry of polyvalent iodine. Chem. Rev. 2008, 108, 5299–5358. [Google Scholar] [CrossRef]
  27. Ochiai, M.; Miyamoto, K. Catalytic version of and reuse in hypervalentorgano-λ3- and -λ5-iodane oxidation. Eur. J. Org. Chem. 2008, 2008, 4229–4239. [Google Scholar] [CrossRef]
  28. Dohi, T.; Kita, Y. Hypervalent iodine reagents as a new entrance to organocatalysts. Chem. Commun. 2009, 2009, 2073–2085. [Google Scholar] [CrossRef]
  29. Uyanik, M.; Ishihara, K. Catalysis with insitu-generated (hypo)iodite ions for oxidative coupling reactions. ChemCatChem 2012, 4, 177–185. [Google Scholar] [CrossRef]
  30. Yakura, T.; Konishi, T. A novel catalytic hypervalent iodine oxidation of p-alkoxyphenols to p-quinones using 4-iodophenoxyacetic acid and Oxone®. Synlett 2007, 2007, 765–768. [Google Scholar] [CrossRef]
  31. Yakura, T.; Yamauchi, Y.; Tian, Y.; Omoto, M. Catalytic hypervalent iodine oxidation of p-dialkoxybenzenes to p-quinones using 4-iodophenoxyacetic acid and Oxone®. Chem. Pharm. Bull. 2008, 56, 1632–1634. [Google Scholar]
  32. Yakura, T.; Tian, Y.; Yamauchi, Y.; Omoto, M.; Konishi, T. Catalytic hypervalent iodine oxidation using 4-iodophenoxyacetic acid and Oxone®: Oxidation of p-alkoxyphenols to p-benzoquinones. Chem. Pharm. Bull. 2009, 57, 252–256. [Google Scholar]
  33. Uyanik, M.; Akakura, M.; Ishihara, K. 2-Iodoxybenzenesulfonic acid as an extremely active catalyst for the selective oxidation of alcohols to aldehydes, ketones, carboxylic acids, and enones with Oxone®. J. Am. Chem. Soc. 2009, 131, 251–262. [Google Scholar] [CrossRef]
  34. Uyanik, M.; Ishihara, K. Hypervalent iodine-mediated oxidation of alcohols. Chem. Commun. 2009, 2009, 2086–2099. [Google Scholar] [CrossRef]
  35. Uyanik, M.; Ishihara, K. 2-Iodoxybenzenesulfonic acid (IBS) catalyzed oxidation of alcohols. Aldrichim. Acta 2010, 43, 83–91. [Google Scholar]
  36. Uyanik, M.; Ishihara, K. 2-Iodoxy-5-methylbenzenesulfonic acid-catalyzed selective oxidation of 4-bromobenzyl alcohol to 4-bromobenzaldehyde or 4-bromobenzoic acid with Oxone®. Org. Syn. 2012, 89, 105–114. [Google Scholar]
  37. Uyanik, M.; Fukatsu, R.; Ishihara, K. IBS-catalyzed oxidative rearrangement of tertiary allylic alcohols to enones with Oxone®. Org. Lett. 2009, 11, 3470–3473. [Google Scholar]
  38. Cui, L.C.; Liu, K.; Zhang, C. Effective oxidation of benzylic and alkane C-H bonds catalyzed by sodium o-iodobenzenesulfonate with Oxone® as a terminal oxidant under phase-transfer conditions. Org. Biomol. Chem. 2011, 9, 2258–2265. [Google Scholar] [CrossRef]
  39. Tanaka, Y.; Ishihara, T.; Konno, T. A new entry for the oxidation of fluoroalkyl-substituted methanol derivatives: Scope and limitation of the organoiodine(V) reagent-catalyzed oxidation. J. Fluor. Chem. 2012, 137, 99–104. [Google Scholar] [CrossRef]
  40. Giurg, M.; Syper, L.; Mlochowski, J. Hydrogen peroxide oxidation of naphthalene derivatives catalyzed by poly(bis-1,2-diphenylene) diselenide. Pol. J. Chem. 2004, 78, 231–238. [Google Scholar]
  41. Carreño, M.C.; Gonzáles-López, M.; Urbano, A. Oxidative de-aromatization of para-alkyl phenols into para-peroxyquinols and para-quinols mediated by Oxone® as a source of singlet oxygen. Angew. Chem. Int. Ed. Engl. 2006, 45, 2737–2741. [Google Scholar]
  42. Ojha, L.R.; Kudugunti, S.; Maddukuri, P.P.; Kommareddy, A.; Gunna, M.R.; Dokuparthi, P.; Gottam, H.B.; Botha, K.K.; Parapati, D.R.; Vinod, T.K. Benzylic carbon oxidation by an in situ formed o-iodoxybenzoic acid (IBX) derivative. Synlett 2009, 2009, 117. [Google Scholar]
  43. Ding, Z.; Xue, S.; Wulff, W.D. A succinct synthesis of the vaulted biarylkigandvanol via a dienone-phenol rearrangement. Chem. Asian J. 2011, 6, 2130–2146. [Google Scholar]
  44. Ludwik, S. The Baeyer-Villiger oxidation of aromatic aldehydes and ketones with hydrogen peroxide catalyzed by selenium compounds. A convenient method for the preparation of phenols. Synthesis 1989, 1989, 167–172. [Google Scholar] [CrossRef]
  45. Bell, K.H.; McCaffery, L.F. Regioselectivemonomethylation of unsymmetrical naphthalenediols with methanolic hydrogen chloride. Aust. J. Chem. 1993, 46, 731–737. [Google Scholar] [CrossRef]
  46. Crich, D.; Zou, Y. Catalytic oxidation adjacent to carbonyl groups and at benzylic positions with a fluorousseleninic acid in the presence of iodoxybenzene. J. Org. Chem. 2005, 70, 3309–3311. [Google Scholar] [CrossRef]
  47. Suchard, O.; Kane, R.; Roe, B.J.; Zimmermann, E.; Jung, C.; Waske, P.A.; Mattay, J.; Oelgemöller, M. Photooxygenations of 1-naphthols: An environmentally friendly access to 1,4-naphthoquinones. Tetrahedron 2006, 62, 1467–1473. [Google Scholar]
  48. Perumal, P.T.; Bhatt, M.V. Oxidation of halophenols and highly substituted phenols with lead(IV) acetate. Synthesis 1980, 1980, 943–945. [Google Scholar] [CrossRef]
  49. Ogata, T.; Okamoto, I.; Kotani, E.; Takeya, T. Biomimetic synthesis of the dinaphthofuranquinone violet-quinone, utilizing oxidative dimerization with the ZrO2/O2 system. Tetrahedron 2004, 60, 3941–3948. [Google Scholar] [CrossRef]
  50. Bernd, P.; Meike, N.; Anja, P. The acid accelerated ruthenium-catalyzed dihydroxylation. Scope and limitations. Org. Biomol. Chem. 2004, 2, 1116–1124. [Google Scholar]
  51. Ratnikov, M.O.; Farkas, L.E.; McLaughlin, E.C.; Chiou, G.; Choi, H.; El-Khalafy, S.H.; Doyle, M.P. Dirhodium-catalyzed phenol and aniline oxidations with T-HYDRO. Substrate scope and mechanism of oxidation. J. Org. Chem. 2011, 76, 2585–2593. [Google Scholar]
  52. Miyamura, H.; Shiramizu, M.; Matsubara, R.; Kobayashi, S. Aerobic Oxidation of Hydroquinone Derivatives Catalyzed by Polymer-Incarcerated Platinum Catalyst. Angew. Chem. Int. Ed. Engl. 2008, 47, 8093–8095. [Google Scholar] [CrossRef]
  53. Lebrasseur, N.; Fan, G.J.; Oxoby, M.; Looney, M.A.; Quideau, S. λ3-Iodane-mediated arenol dearomatization. Synthesis of five-membered ring-containing analogues of the aquayamycin ABC tricyclic unit and novel access to the apoptosis inducer menadione. Tetrahedron 2005, 61, 1551–1562. [Google Scholar] [CrossRef]
  • Sample Availability: Samples of the compounds 1a–c are available from the authors.

Share and Cite

MDPI and ACS Style

Uyanik, M.; Mutsuga, T.; Ishihara, K. IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone®. Molecules 2012, 17, 8604-8616. https://doi.org/10.3390/molecules17078604

AMA Style

Uyanik M, Mutsuga T, Ishihara K. IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone®. Molecules. 2012; 17(7):8604-8616. https://doi.org/10.3390/molecules17078604

Chicago/Turabian Style

Uyanik, Muhammet, Tatsuya Mutsuga, and Kazuaki Ishihara. 2012. "IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone®" Molecules 17, no. 7: 8604-8616. https://doi.org/10.3390/molecules17078604

Article Metrics

Back to TopTop