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DOI: 10.1055/s-0036-1588575
Oxidation of Organosulfides to Organosulfones with Trifluoromethyl 3-Oxo-1λ3,2-benziodoxole-1(3H)-carboxylate as an Oxidant
Publikationsverlauf
Received: 02. August 2017
Accepted after revision: 29. August 2017
Publikationsdatum:
21. September 2017 (online)
Abstract
An alternative approach is described for the oxidation of organosulfides to the corresponding organosulfones by using trifluoromethyl 3-oxo-1λ3,2-benziodoxole-1(3H)-carboxylate as an oxidant. The oxidation of the sulfides was performed by using 2.4 equivalents of the oxidant in refluxing acetonitrile. The oxidation products were isolated in good to excellent yields.
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Organosulfones are important scaffolds in medicinal[1] and natural-product chemistry.[2] The presence of a sulfone functionality makes these compounds more suitable as synthetic intermediates and as chemical building blocks for many biologically active compounds, for example 1–6 (Figure [1]). Rofecoxib (Vioxx; 1) has been introduced as a COX-2 inhibitor and is a potent anti-inflammatory drug[3] and an analgesic.[4] Laropiprant (2) is a prostaglandin D2 receptor antagonist.[5] Dapson (3) and sulfamethoxazole (4) have been developed as potent antibiotics for the treatment of leprosy and urinary infections, respectively.[6] [7] Glyburide (5) has been developed as a second-generation sulfonylurea, and is used in treating type 2 diabetes by enhancing insulin secretion.[8] Carbutamide (6) is classed as a first-generation sulfonylurea, and is also used as an antidiabetic agent.[9] In addition, various naturally occurring garlicnins isolated from Allium sativum L. have been shown to prevent cancer-cell growth.[2]
Numerous procedures have been developed for the oxidation of sulfides to sulfoxides and sulfones by various oxidants.[10] [11] [12] In most of these approaches, oxidation of sulfides has been achieved by using various transition-metal derivatives, including Ti,[13] Sc,[10b] Ru,[14] Mn,[15] Zr,[16] Cu,[17] or Fe[18] complexes. In addition, several metal-free approaches have also been reported.[19] [20] Most oxidation approaches, however, involve the use of toxic metals or harsh reaction conditions. Recently, a synthesis of sulfones has been developed by using hypervalent iodine salts.[21]
In the past few decades, the chemistry of hypervalent iodine reagents has received attention due to their favorable safety profile and ease of handling.[22] [23] 1-Hydroxy-1λ3,2-benziodoxol-3(1H)-one 1-oxide (IBX) is one of the most common hypervalent iodine reagents, and it has been used in various oxidation reactions.[24] [25] Despite being a versatile oxidant, IBX has several drawbacks, such as poor solubility in common organic solvents[26] and a tendency to explode at elevated temperatures,[27] which limit its applications. We synthesized trifluoromethyl 3-oxo-1λ3,2-benziodoxole-1(3H)-carboxylate (8) by the oxidation of 2-iodobenzoic acid (7) with Oxone as oxidant in the presence of TFA (Scheme [1]).[28] The synthesis of compound 8 has been reported previously,[29] but its oxidative properties are still unexplored.
Herein, we report the selective oxidation of sulfides 9 to the corresponding sulfones 10 by using benziodoxole 8 as an oxidant. The precursors 9a–c were synthesized by the reaction of the corresponding thiophenols with t-butanol in the presence of an acid.[30a] Other starting materials 9d–h were synthesized by the reaction of thiophenols with alkyl bromides in the presence of sodium ethoxide.[30b]
Initially, our efforts were directed at optimizing reaction conditions for the oxidation of tert-butyl phenyl sulfide (9a) as a model substrate. When the oxidation of sulfide 9a was performed with 1.0 equivalents of benziodoxole 8 in acetonitrile at room temperature for 36 hours, the oxidation product 10a was not obtained (Table [1], entry 1). When the same reaction was performed at the reflux temperature, conversion of the starting material was observed, and tert-butyl phenyl sulfide (10a) was obtained in 40% yield (entry 2). The oxidation product 10a was isolated in 56% yield when 1.5 equivalents of reagent 8 were used (entry 3). In this reaction, full conversion was not observed, and 40% of the starting material was recovered. When reactions were carried out by using 2.0 or 2.4 equivalents of 8, product 10a was obtained 80 and 85% yield, respectively (entries 4 and 5). When the reaction was performed with 3.0 equivalents of 8, no significant improvement was observed, and 10a was isolated in 86% yield (entry 6).
Next, our efforts were directed toward the optimization of the solvent. Various polar and nonpolar solvents were investigated for the oxidation of sulfide 9a (Table [2]). Initially, the oxidation was performed in MeCN, and oxidation product 10a was isolated in 85% yield (Table [2], entry 1). The oxidation proceeded well in the polar aprotic solvents DMSO and dichloromethane, giving 10a in 65 and 60% yield, respectively (entries 2 and 3). In the polar protic solvents methanol and ethanol, 10a was obtained in 50 and 52% yield, respectively (Table [2], entries 4 and 5). When the oxidation was performed in THF or 1,3-dioxane, 10a was obtained in 43 and 30% yield, respectively (entries 6 and 7). Therefore, the use of 2.4 equivalents of 8 in acetonitrile at the reflux for 16 hours was concluded to be optimal for the oxidation of sulfide 9a to the corresponding sulfone 10a.
a The reaction was performed at 100 °C.
A series of sulfides 9b–h was then successfully oxidized to the corresponding sulfones 10b–h in 68–91% yield under the optimized conditions (Table [3], entries 1–8).[31] All the oxidation reactions proceeded well, and both electron-withdrawing and electron-donating aromatic substituents were tolerated. The oxidation products were isolated in slightly better yields with substrates having electron-donating groups on the aromatic ring in comparison to substrates bearing electron-withdrawing groups.
Next, we examined the selectivity of 8 towards the oxidation of sulfoxides and sulfides. To check the selectivity, a competitive reaction was performed between sulfide 9a and sulfoxide 11 in acetonitrile at the reflux temperature. Sulfoxide 11 was synthesized by the oxidation of sulfide 9c with m-CPBA at low temperature.[32] Sulfide 9a was oxidized to the corresponding sulfone 10a in 16 hours, whereas the oxidation of sulfoxide 11 to sulfone 10c was completed in eight hours. After the purification, sulfone 10a was isolated in 82% yield, and sulfone 10c was obtained in 89% yield (Scheme [2]). The results of the competitive reaction suggest that reagent 8 can be used for the oxidation of either sulfides or sulfoxides to sulfones, but the oxidation of sulfoxides is selective over that of sulfides.
In conclusion, we have developed an alternative approach for the oxidation of organosulfides to the corresponding organosulfones by using trifluoromethyl 3-oxo-1λ3,2-benziodoxole-1(3H)-carboxylate as an oxidant. This is the first report of the use of this compound as an oxidant.
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Acknowledgements
Financial support by the DST, New Delhi, is gratefully acknowledged. We thank the SAIF Department, VIT Vellore, for the analytical data.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0036-1588575.
- Supporting Information
-
References and Notes
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- 1c Pal M. RaoVeeramaneni V. Nagabelli M. RaoKalleda S. Misra P. RaoCasturi S. Rao Veleswarapu K. Bioorg. Med. Chem. Lett. 2003; 13: 1639
- 1d Otzen T. Wempe EG. Kunz B. Bartels R. Lehwark-Yvetot G. Hänsel W. Schaper K.-J. Seydel JK. J. Med. Chem. 2003; 47: 240
- 1e Doherty GA. Kamenecka T. McCauley E. Van Riper G. Mumford RA. Tong S. Hagmann WK. Bioorg. Med. Chem. Lett. 2002; 12: 729
- 2 Nohara T. Fujiwara Y. Ikeda T. Murakami K. Ono M. Nakano D. Kinjo J. Chem. Pharm. Bull. 2013; 61: 695
- 3 Sang Y. Connor DT. Doubleday R. Sorenson RJ. Sercel AD. Unangst PC. Roth BD. Gilbertsen RB. Chan K. Schrier DJ. Guglietta A. Bornemeier DA. Dyer RD. J. Med. Chem. 1999; 42: 1151
- 4 Tozkoparan B. Küpeli E. Yeşilada E. Ertan M. Bioorg. Med. Chem. 2007; 15: 1808
- 5a Zhou H. Zhu Q. Gan Z. Dong G. Xu Y. Med. Chem. Res. 2015; 24: 3920
- 5b Sturino FC. Neill OG. Lachance N. Boyd M. Berthelette C. Labelle M. Li L. Roy B. Scheigetz J. Tsou N. Aubin Y. Bateman KP. Chauret N. Day SH. Levesque J.-F. Seto C. Silva JH. Trimble LA. Carriere M.-C. Denis D. Greig G. Kargman S. Lamontagne S. Matheiu M.-C. Sawyer N. Slipetz D. Abraham WM. Jones T. McAuliffe M. Piechuta H. Nicoll-Griffith DA. Wang Z. Zamboni R. Young RN. Metters KM. J. Med. Chem. 2007; 50: 794
- 6 Yazdanyar S. Boer J. Ingvarsson G. Szepietowski JC. Jemec GB. E. Dermatology (Basel, Switz.) 2011; 222: 342 ; DOI: 10.1159/000329023
- 7 Sunduru N. Salin O. Gylfe A. Elofsson M. Eur. J. Med. Chem. 2015; 101: 595 ; and references cited therein
- 8 Zhao J. Li Z. Song S. Wang M.-A. Fu B. Zhang Z. Angew. Chem. Int. Ed. 2016; 55: 5545 ; and references cited therein
- 9 El-Kerdawy MM. Selim HA. J. Drug Res. 1973; 5: 135
- 10a Sharipov AK. Russ. J. Appl. Chem. 2003; 76: 108 ; DOI: 10.1023/A:1023308303
- 10b Matteucci M. Bhalay G. Bradley M. Org. Lett. 2003; 5: 235
- 11 Sun J. Zhu C. Dai Z. Yang M. Pan Y. Hu H. J. Org. Chem. 2004; 69: 8500
- 12 Mba M. Prins LJ. Licini G. Org. Lett. 2007; 9: 21
- 13a Gao J. Guo H. Liu S. Wang M. Tetrahedron Lett. 2007; 48: 8453
- 13b Khedher I. Ghorbel A. J. Porous Mater. 2010; 17: 501
- 14 Li T.-T. Li F.-M. Zhao W.-L. Tian Y.-H. Chen Y. Cai R. Fu W.-F. Inorg. Chem. 2015; 54: 183
- 15 Bagherzadeh M. Latifi R. Tahsini L. Amini M. Catal. Commun. 2008; 10: 196
- 16 Bonchio M. Licini G. Di Furia F. Mantovani S. Modena G. Nugent WA. J. Org. Chem. 1999; 64: 1326
- 17 Liu R. Wu L.-z. Feng X.-m. Zhang Z. Li Y.-z. Wang Z.-l. Inorg. Chim. Acta 2007; 360: 656
- 18 Egami H. Katsuki T. J. Am. Chem. Soc. 2007; 129: 8940
- 19 Wagh RB. Nagarkar JM. Catal. Lett. 2017; 147: 181
- 20 Rostami A. Navasi Y. Moradi D. Ghorbani-Choghamarani A. Catal. Commun. 2014; 43: 16
- 21a Umierski N. Manolikakes G. Org. Lett. 2013; 15: 188
- 21b Margraf N. Manolikakes G. J. Org. Chem. 2015; 80: 2582
- 22a Yoshimura A. Zhdankin VV. Chem. Rev. 2016; 116: 3328
- 22b Singh FV. Wirth T. In Comprehensive Organic Synthesis II . Vol. 7, Chap. 7.29. Knochel P. Molander GA. Elsevier; Amsterdam: 2014: 880
- 22c Zhdankin VV. J. Org. Chem. 2011; 76: 1185
- 22d Merritt EA. Olofsson B. Angew. Chem. 2009; 121: 9214 ; Angew. Chem. Int. Ed. 2009, 48, 9052
- 22e Zhdankin VV. ARKIVOC 2009; (i): 1
- 22f Farooq U. Shah AA. Wirth T. Angew. Chem. 2009; 121: 1036 ; Angew. Chem. Int. Ed. 2009, 48, 1018
- 22g Zhdankin VV. Stang PJ. Chem. Rev. 2008; 108: 5299
- 22h Ladziata U. Zhdankin VV. Synlett 2007; 527
- 22i Wirth T. Angew. Chem. 2005; 117: 3722 ; Angew. Chem. Int. Ed. 2005, 44, 3656
- 22j Moriarty RM. J. Org. Chem. 2005; 70: 2893
- 22k Wirth T. In Organic Synthesis Highlights V . Schmalz H.-G. Wirth T. Wiley-VCH; Weinheim: 2003: 144
- 22l Wirth T. Hypervalent Iodine Chemistry: Modern Developments in Organic Synthesis. Springer; Berlin: 2003
- 22m Zhdankin VV. Chem. Rev. 2002; 102: 2523
- 22n Wirth T. Angew. Chem. 2001; 113: 2893 ; Angew. Chem. Int. Ed. 2001, 40, 2812
- 23a Qian G. Liu B. Tan Q. Zhang S. Xu B. Eur. J. Org. Chem. 2014; 4837
- 23b Mizar P. Wirth T. Angew. Chem. 2014; 6103 ; Angew. Chem. Int. Ed. 2014, 53, 5993
- 23c Singh FV. Wirth T. Synthesis 2013; 45: 2499 ; and references are cited therein
- 23d Singh FV. Rehbein J. Wirth T. ChemistryOpen 2012; 1: 245
- 23e Kajiyama D. Saitoh T. Yamaguchi S. Nishiyama S. Synthesis 2012; 44: 1667
- 23f Paz NR. Santana AG. Francisco CG. Suárez E. González CC. Org. Lett. 2012; 14: 3388
- 23g Wardrop DJ. Yermolina MV. Bowen EG. Synthesis 2012; 44: 1199
- 23h Singh FV. Wirth T. Org. Lett. 2011; 13: 6504
- 23i Du X. Chen H. Chen Y. Chen J. Liu Y. Synlett 2011; 1010
- 23j Wang H. Fan R. J. Org. Chem. 2010; 75: 6994
- 23k Moriarty RM. Tyagi S. Kinch M. Tetrahedron 2010; 66: 5801
- 23l Bose SS. Idrees M. Synthesis 2010; 398
- 23m Pardo LM. Tellitu I. Domínguez E. Synthesis 2010; 971
- 24a Xie A. Zhou X. Feng L. Hu X. Dong W. Tetrahedron 2014; 70: 3514
- 24b Xu S. Itto K. Satoh M. Arimoto H. Chem. Commun. 2014; 50: 2758
- 25 Matassini C. Parmeggiani C. Cardona F. Goti A. Org. Lett. 2015; 17: 4082
- 26 CAUTION! IBX and Dess–Martin periodinane are explosive upon impact or heating at >200 °C; see: Plumb JB. Harper DJ. Chem. Eng. News 1990; 68: 3 DOI: 10.1021/cen-v068n029.p002
- 27a More JD. Finney NS. Org. Lett. 2002; 4: 3001
- 27b Nicolaou KC. Baran PS. Zhong Y.-L. J. Am. Chem. Soc. 2001; 123: 3183
- 27c Nicolaou KC. Zhong Y.-L. Baran PS. J. Am. Chem. Soc. 2000; 122: 7596
- 28 Zagulyaeva AA. Yusubov MS. Zhdankin VV. J. Org. Chem. 2010; 75: 2119
- 29a Kasumov TM. Brel VK. Grishin YK. Zefirov NS. Stang PJ. Tetrahedron 1997; 53: 1145
- 29b Page TK. Wirth T. Synthesis 2006; 3153
- 30a Freudendahl DM. Iwaoka M. Wirth T. Eur. J. Org. Chem. 2010; 3934
- 30b O’Mahony GE. Ford A. Maguire AR. J. Org. Chem. 2012; 77: 3288
- 31 Sulfones 10a–h; General Procedure A mixture of the appropriate sulfide 9 (0.5 mmol) and benziodoxole 8 (413 mg, 2.4 equiv) in MeCN (3 mL) was refluxed for 16–20 h. When the reaction was complete (TLC), sat. aq NaHCO3 (5 mL) was added and the mixture was extracted with EtOAc (3 × 15 mL). The organic layers were combined, dried (Na2SO4), filtered, and concentrated under vacuum. The crude product was purified by column chromatography [silica gel, EtOAc–hexane (1:3)]. tert-Butyl Phenyl Sulfone (10a) 22b White solid; yield: 84 mg (0.42 mmol, 85%); mp; 90–92 °C. IR (film): 697, 725, 749, 764, 802, 996, 1021, 1076, 1130, 1277, 1294, 1449, 1475 cm–1. 1H NMR (400 MHz, CDCl3): δ = 1.23 (s, 9 H, t-Bu), 7.46 (t, J = 7.6 Hz, 2 H, ArH), 7.56 (t, J = 7.6 Hz, 1 H, ArH), 7.77 (d, J = 7.6 Hz, 2 H, ArH). 13C NMR (100 MHz, CDCl3): δ = 23.5, 59.7, 128.7, 130.3, 133.6, 135.2. GC/MS: m/z (%) = 198(5), 143(25), 79(13), 77(50), 58(29), 57(100), 51(51), 41(50).
- 32 Mangaonkar SR. Singh FV. Der Pharma Chem. 2016; 8: 419
-
References and Notes
- 1a Xu F. Chen Y. Fan E. Sun Z. Org. Lett. 2016; 18: 2777
- 1b Hartz RA. Arvanitis AG. Arnold C. Rescinito JP. Hung KL. Zhang G. Wong H. Langley DR. Gilligan PJ. Trainor GL. Bioorg. Med. Chem. Lett. 2006; 16: 934
- 1c Pal M. RaoVeeramaneni V. Nagabelli M. RaoKalleda S. Misra P. RaoCasturi S. Rao Veleswarapu K. Bioorg. Med. Chem. Lett. 2003; 13: 1639
- 1d Otzen T. Wempe EG. Kunz B. Bartels R. Lehwark-Yvetot G. Hänsel W. Schaper K.-J. Seydel JK. J. Med. Chem. 2003; 47: 240
- 1e Doherty GA. Kamenecka T. McCauley E. Van Riper G. Mumford RA. Tong S. Hagmann WK. Bioorg. Med. Chem. Lett. 2002; 12: 729
- 2 Nohara T. Fujiwara Y. Ikeda T. Murakami K. Ono M. Nakano D. Kinjo J. Chem. Pharm. Bull. 2013; 61: 695
- 3 Sang Y. Connor DT. Doubleday R. Sorenson RJ. Sercel AD. Unangst PC. Roth BD. Gilbertsen RB. Chan K. Schrier DJ. Guglietta A. Bornemeier DA. Dyer RD. J. Med. Chem. 1999; 42: 1151
- 4 Tozkoparan B. Küpeli E. Yeşilada E. Ertan M. Bioorg. Med. Chem. 2007; 15: 1808
- 5a Zhou H. Zhu Q. Gan Z. Dong G. Xu Y. Med. Chem. Res. 2015; 24: 3920
- 5b Sturino FC. Neill OG. Lachance N. Boyd M. Berthelette C. Labelle M. Li L. Roy B. Scheigetz J. Tsou N. Aubin Y. Bateman KP. Chauret N. Day SH. Levesque J.-F. Seto C. Silva JH. Trimble LA. Carriere M.-C. Denis D. Greig G. Kargman S. Lamontagne S. Matheiu M.-C. Sawyer N. Slipetz D. Abraham WM. Jones T. McAuliffe M. Piechuta H. Nicoll-Griffith DA. Wang Z. Zamboni R. Young RN. Metters KM. J. Med. Chem. 2007; 50: 794
- 6 Yazdanyar S. Boer J. Ingvarsson G. Szepietowski JC. Jemec GB. E. Dermatology (Basel, Switz.) 2011; 222: 342 ; DOI: 10.1159/000329023
- 7 Sunduru N. Salin O. Gylfe A. Elofsson M. Eur. J. Med. Chem. 2015; 101: 595 ; and references cited therein
- 8 Zhao J. Li Z. Song S. Wang M.-A. Fu B. Zhang Z. Angew. Chem. Int. Ed. 2016; 55: 5545 ; and references cited therein
- 9 El-Kerdawy MM. Selim HA. J. Drug Res. 1973; 5: 135
- 10a Sharipov AK. Russ. J. Appl. Chem. 2003; 76: 108 ; DOI: 10.1023/A:1023308303
- 10b Matteucci M. Bhalay G. Bradley M. Org. Lett. 2003; 5: 235
- 11 Sun J. Zhu C. Dai Z. Yang M. Pan Y. Hu H. J. Org. Chem. 2004; 69: 8500
- 12 Mba M. Prins LJ. Licini G. Org. Lett. 2007; 9: 21
- 13a Gao J. Guo H. Liu S. Wang M. Tetrahedron Lett. 2007; 48: 8453
- 13b Khedher I. Ghorbel A. J. Porous Mater. 2010; 17: 501
- 14 Li T.-T. Li F.-M. Zhao W.-L. Tian Y.-H. Chen Y. Cai R. Fu W.-F. Inorg. Chem. 2015; 54: 183
- 15 Bagherzadeh M. Latifi R. Tahsini L. Amini M. Catal. Commun. 2008; 10: 196
- 16 Bonchio M. Licini G. Di Furia F. Mantovani S. Modena G. Nugent WA. J. Org. Chem. 1999; 64: 1326
- 17 Liu R. Wu L.-z. Feng X.-m. Zhang Z. Li Y.-z. Wang Z.-l. Inorg. Chim. Acta 2007; 360: 656
- 18 Egami H. Katsuki T. J. Am. Chem. Soc. 2007; 129: 8940
- 19 Wagh RB. Nagarkar JM. Catal. Lett. 2017; 147: 181
- 20 Rostami A. Navasi Y. Moradi D. Ghorbani-Choghamarani A. Catal. Commun. 2014; 43: 16
- 21a Umierski N. Manolikakes G. Org. Lett. 2013; 15: 188
- 21b Margraf N. Manolikakes G. J. Org. Chem. 2015; 80: 2582
- 22a Yoshimura A. Zhdankin VV. Chem. Rev. 2016; 116: 3328
- 22b Singh FV. Wirth T. In Comprehensive Organic Synthesis II . Vol. 7, Chap. 7.29. Knochel P. Molander GA. Elsevier; Amsterdam: 2014: 880
- 22c Zhdankin VV. J. Org. Chem. 2011; 76: 1185
- 22d Merritt EA. Olofsson B. Angew. Chem. 2009; 121: 9214 ; Angew. Chem. Int. Ed. 2009, 48, 9052
- 22e Zhdankin VV. ARKIVOC 2009; (i): 1
- 22f Farooq U. Shah AA. Wirth T. Angew. Chem. 2009; 121: 1036 ; Angew. Chem. Int. Ed. 2009, 48, 1018
- 22g Zhdankin VV. Stang PJ. Chem. Rev. 2008; 108: 5299
- 22h Ladziata U. Zhdankin VV. Synlett 2007; 527
- 22i Wirth T. Angew. Chem. 2005; 117: 3722 ; Angew. Chem. Int. Ed. 2005, 44, 3656
- 22j Moriarty RM. J. Org. Chem. 2005; 70: 2893
- 22k Wirth T. In Organic Synthesis Highlights V . Schmalz H.-G. Wirth T. Wiley-VCH; Weinheim: 2003: 144
- 22l Wirth T. Hypervalent Iodine Chemistry: Modern Developments in Organic Synthesis. Springer; Berlin: 2003
- 22m Zhdankin VV. Chem. Rev. 2002; 102: 2523
- 22n Wirth T. Angew. Chem. 2001; 113: 2893 ; Angew. Chem. Int. Ed. 2001, 40, 2812
- 23a Qian G. Liu B. Tan Q. Zhang S. Xu B. Eur. J. Org. Chem. 2014; 4837
- 23b Mizar P. Wirth T. Angew. Chem. 2014; 6103 ; Angew. Chem. Int. Ed. 2014, 53, 5993
- 23c Singh FV. Wirth T. Synthesis 2013; 45: 2499 ; and references are cited therein
- 23d Singh FV. Rehbein J. Wirth T. ChemistryOpen 2012; 1: 245
- 23e Kajiyama D. Saitoh T. Yamaguchi S. Nishiyama S. Synthesis 2012; 44: 1667
- 23f Paz NR. Santana AG. Francisco CG. Suárez E. González CC. Org. Lett. 2012; 14: 3388
- 23g Wardrop DJ. Yermolina MV. Bowen EG. Synthesis 2012; 44: 1199
- 23h Singh FV. Wirth T. Org. Lett. 2011; 13: 6504
- 23i Du X. Chen H. Chen Y. Chen J. Liu Y. Synlett 2011; 1010
- 23j Wang H. Fan R. J. Org. Chem. 2010; 75: 6994
- 23k Moriarty RM. Tyagi S. Kinch M. Tetrahedron 2010; 66: 5801
- 23l Bose SS. Idrees M. Synthesis 2010; 398
- 23m Pardo LM. Tellitu I. Domínguez E. Synthesis 2010; 971
- 24a Xie A. Zhou X. Feng L. Hu X. Dong W. Tetrahedron 2014; 70: 3514
- 24b Xu S. Itto K. Satoh M. Arimoto H. Chem. Commun. 2014; 50: 2758
- 25 Matassini C. Parmeggiani C. Cardona F. Goti A. Org. Lett. 2015; 17: 4082
- 26 CAUTION! IBX and Dess–Martin periodinane are explosive upon impact or heating at >200 °C; see: Plumb JB. Harper DJ. Chem. Eng. News 1990; 68: 3 DOI: 10.1021/cen-v068n029.p002
- 27a More JD. Finney NS. Org. Lett. 2002; 4: 3001
- 27b Nicolaou KC. Baran PS. Zhong Y.-L. J. Am. Chem. Soc. 2001; 123: 3183
- 27c Nicolaou KC. Zhong Y.-L. Baran PS. J. Am. Chem. Soc. 2000; 122: 7596
- 28 Zagulyaeva AA. Yusubov MS. Zhdankin VV. J. Org. Chem. 2010; 75: 2119
- 29a Kasumov TM. Brel VK. Grishin YK. Zefirov NS. Stang PJ. Tetrahedron 1997; 53: 1145
- 29b Page TK. Wirth T. Synthesis 2006; 3153
- 30a Freudendahl DM. Iwaoka M. Wirth T. Eur. J. Org. Chem. 2010; 3934
- 30b O’Mahony GE. Ford A. Maguire AR. J. Org. Chem. 2012; 77: 3288
- 31 Sulfones 10a–h; General Procedure A mixture of the appropriate sulfide 9 (0.5 mmol) and benziodoxole 8 (413 mg, 2.4 equiv) in MeCN (3 mL) was refluxed for 16–20 h. When the reaction was complete (TLC), sat. aq NaHCO3 (5 mL) was added and the mixture was extracted with EtOAc (3 × 15 mL). The organic layers were combined, dried (Na2SO4), filtered, and concentrated under vacuum. The crude product was purified by column chromatography [silica gel, EtOAc–hexane (1:3)]. tert-Butyl Phenyl Sulfone (10a) 22b White solid; yield: 84 mg (0.42 mmol, 85%); mp; 90–92 °C. IR (film): 697, 725, 749, 764, 802, 996, 1021, 1076, 1130, 1277, 1294, 1449, 1475 cm–1. 1H NMR (400 MHz, CDCl3): δ = 1.23 (s, 9 H, t-Bu), 7.46 (t, J = 7.6 Hz, 2 H, ArH), 7.56 (t, J = 7.6 Hz, 1 H, ArH), 7.77 (d, J = 7.6 Hz, 2 H, ArH). 13C NMR (100 MHz, CDCl3): δ = 23.5, 59.7, 128.7, 130.3, 133.6, 135.2. GC/MS: m/z (%) = 198(5), 143(25), 79(13), 77(50), 58(29), 57(100), 51(51), 41(50).
- 32 Mangaonkar SR. Singh FV. Der Pharma Chem. 2016; 8: 419