Unified Oxidation Protocol for the Synthesis of Carbonyl Compounds Using a Manganese Catalyst

Abstract

We have developed a unified protocol for the oxidation of ethers, benzylic compounds, and alcohols to carbonyl compounds. The protocol uses catalytic amounts of manganese(II) chloride tetrahydrate and 4,4′,4′′-tri(t-butyl)-2,2′:6′,2′′-terpyridine in combination with a stoichiometric amount of either m-chloroperbenzoic acid (MCPBA) or potassium hydrogen peroxysulfate (KHSO₅). A reagent system consisting of the Mn catalyst and MCPBA­ permitted the chemoselective sp^³ C-H oxidation of alkyl ethers and benzylic compounds to generate the corresponding ketones. Alternatively, the water-soluble inorganic salt KHSO₅ in combination with the Mn catalyst was used to oxidize alcohols to ketones or carboxylic acids. Importantly, the Mn catalyst/KHSO₅ system eliminates technical difficulties associated with the isolation of carboxylic acid products. All the oxidations presented in this feature article proceed at sub-ambient temperature in an aerobic atmosphere, and can therefore be used in practical syntheses of complex organic molecules.

Key words

catalysis - oxidation - ethers - alcohols - ketones - carboxylic acids

References

• 1a Ley SV. In Comprehensive Organic Synthesis   Vol.7:  Trost BM. Fleming I. Pergamon; Oxford: 1991. 
• 1b Handbook of Reagents for Organic Synthesis: Oxidizing and Reducing Agents   Burke SD. Danheiser RL. Wiley; Chichester: 1999. 
• 2a Activation and Functionalization of C-H Bonds   Goldberg KI. Goldman AS. American Chemical Society; Washington DC: 2004. 
• 2b Handbook of C-H Transformations   Vols. 1 and 2:  Dyker G. Wiley-VCH; Weinheim: 2005. 
• 2c Handbook of Reagents for Organic Synthesis: Reagents for Direct Functionalization of C-H Bonds   Paquette LA. Fuchs PL. Wiley; Chichester: 2007. 
• For recent reviews on direct sp^³ C-H transformations, see:
• 3a Naota T. Takaya H. Murahashi S.-I. Chem. Rev.  1998,  98:  2599 
• 3b Costas M. Mehn MP. Jensen MP. Que L. Chem. Rev.  2004,  104:  939 
• 3c Davies HML. Long MS. Angew. Chem. Int. Ed.  2005,  44:  3518 
• 3d Godula K. Sames D. Science  2006,  312:  67 
• 3e Dick AR. Sanford MS. Tetrahedron  2006,  62:  2439 
• 3f Davies HML. Angew. Chem. Int. Ed.  2006,  45:  6422 
• 3g Christmann M. Angew. Chem. Int. Ed.  2008,  47:  2740 
• 3h Li C.-J. Acc. Chem. Res.  2009,  42:  335 
• 3i Daugulis O. Do H.-Q. Shabashov D. Acc. Chem. Res.  2009,  42:  1074 
• 3j Giri R. Shi B.-F. Engle KM. Maugel N. Yu J.-Q. Chem. Soc. Rev.  2009,  38:  3242 
• For recent representative examples of direct C-H oxidation, see:
• 4a Ohtake H. Higuchi T. Hirobe M. J. Am. Chem. Soc.  1992,  114:  10660 
• 4b Kaufman MD. Grieco PA. Bougie DW. J. Am. Chem. Soc.  1993,  115:  11648 
• 4c Groves JT. Bonchio M. Carofiglio T. Shalyaev K. J. Am. Chem. Soc.  1996,  118:  8961 
• 4d Shingaki T. Miura K. Higuchi T. Hirobe M. Nagano T. Chem. Commun.  1997,  861 
• 4e Kim C. Chen K. Kim J. Que L. J. Am. Chem. Soc.  1997,  119:  5964 
• 4f Breslow R. Huang Y. Zhang X. Yang J. Proc. Natl. Acad. Sci. U.S.A.  1997,  94:  11156 
• 4g Arnone A. Foletto S. Metrangolo P. Pregnolato M. Resnati G. Org. Lett.  1999,  1:  281 
• 4h Desai LV. Hull KL. Sanford MS. J. Am. Chem. Soc.  2004,  126:  9542 
• 4i Reddy BVS. Reddy LR. Corey EJ. Org. Lett.  2006,  8:  3391 
• 4j Chen MS. White MC. Science  2007,  318:  783 
• 4k Nizova GV. Shul’pin GB. Tetrahedron  2007,  63:  7997 
• 4l Chen K. Richter JM. Baran PS. J. Am. Chem. Soc.  2008,  130:  7247 
• 4m Chen K. Baran PS. Nature  2009,  459:  824 
• 4n Litvinas ND. Brodsky BH. Du Bois J. Angew. Chem. Int. Ed.  2009,  48:  4513 
• 4o Chen K. Eschenmoser A. Baran PS. Angew. Chem. Int. Ed.  2009,  48:  9705 
• 4p Chen MS. White MC. Science  2010,  327:  566 
• 6 Kamijo S. Amaoka Y. Inoue M. Chem. Asian J.  2010,  5:  486 
• 7a Handbook of Reagents for Organic Synthesis: Activating Agents and Protecting Groups   Pearson AJ. Roush WR. Wiley; Chichester: 1999. 
• 7b Kociénski PJ. Protecting Groups   Thieme; Stuttgart: 2000. 
• 7c Greene TW. Wuts PGM. Protective Groups in Organic Synthesis   Wiley; New York: 2007. 
• For representative applications of methyl ethers as a synthetic intermediate in total syntheses, see:
• 8a Corey EJ. Hong B. J. Am. Chem. Soc.  1994,  116:  3149 
• 8b Overman LE. Ricca DJ. Tran VD. J. Am. Chem. Soc.  1997,  119:  12031 
• 8c Pattenden G. Gonzalez MA. MuCulloch S. Walter A. Woodhead SJ. Proc. Natl. Acad. Sci. U.S.A.  2004,  101:  12024 
• 8d Overman LE. Velthuisen EJ. J. Org. Chem.  2006,  71:  1581 
• 9a Godfrey CRA. In Comprehensive Organic Synthesis   Vol. 7:  Trost BM. Fleming I. Pergamon; Oxford: 1991.  Chap. 2.6. p.235-240  ; and references therein
• 9b Larock RC. Comprehensive Organic Transformations   Wiley-VCH; New York: 1999.  p.1641-1645  
• 10a Curci R. D’Accolti L. Fiorentino M. Fusco C. Adam W. González-Nuñez ME. Mello R. Tetrahedron Lett.  1992,  33:  4225 
• 10b van Heerden FR. Dixon JT. Holzapfel CW. Tetrahedron Lett.  1992,  33:  7399 
• 11 Arnone A. Bernardi R. Cavicchioli M. Resnati G.
  J. Org. Chem.  1995,  60:  2314 
• For Ru-catalyzed oxidation of acyclic ethers, see:
• 12a Carlsen PHJ. Katsuki T. Martin VS. Sharpless KB. J. Org. Chem.  1981,  46:  3936 
• 12b Schuda PF. Cichowicz MB. Heimann MR. Tetrahedron Lett.  1983,  24:  3829 
• For examples of direct methyl ether oxidation, see:
• 13a Bach RD. Taaffee TH. Holubka JW. J. Org. Chem.  1980,  45:  3439 
• 13b Olah GA. Gupta BGB. Fung AP. Synthesis  1980,  897 
• 13c Nishiguchi T. Bougauchi M.
  J. Org. Chem.  1990,  55:  5606 
• 13d Rozen S. Dayan S. Bareket Y. J. Org. Chem.  1995,  60:  8267 
• 13e Suzuki H. Takeuchi T. Mori T. Bull. Chem. Soc. Jpn.  1997,  70:  3111 
• 14a Chen H. Tagore R. Das S. Incarvito C. Faller JW. Crabtree RH. Brudvig GW. Inorg. Chem.  2005,  44:  7661 
• 14b Das S. Incarvito CD. Crabtree RH. Brudvig GW. Science  2006,  312:  1941 
• 14c Das S. Brudvig GW. Crabtree RH. J. Am. Chem. Soc.  2008,  130:  1628 
• For recent reports on Mn-catalyzed epoxidation in similar systems, see:
• 15a Murphy A. Stack SP. J. Mol. Catal. A: Chem.  2006,  251:  78 
• 15b Kang B. Kim M. Lee J. Do Y. Chang S. J. Org. Chem.  2006,  71:  6721 
• 15c Nehru K. Kim SJ. Kim IY. Seo MS. Kim Y. Kim S.-J. Kim J. Nam W. Chem. Commun.  2007,  4623 
• 15d Guillemot G. Neuburger M. Pfaltz A. Chem. Eur. J.  2007,  13:  8960 
• 15e Ilyashenko G. Sale D. Motevalli M. Watkinson M.
  J. Mol. Catal. A: Chem.  2008,  296:  1 
• 15f Ho K.-P. Wong W.-L. Lam K.-M. Lai C.-P. Chan TH. Wong K.-Y. Chem. Eur. J.  2008,  14:  7988 
• 15g Garcia-Bosch I. Company A. Fontrodona X. Ribas X. Costas M. Org. Lett.  2008,  10:  2095 
• 16a Duncan TV. Ishizuka T. Therien M. J. Am. Chem. Soc.  2007,  129:  9691 
• 16b Arzoumanian H. Bakhtchadjian R. Agrifoglio G. Atencio R. Briceño A. Transition Met. Chem. (Dordrecht, Neth.)  2006,  31:  681 
• 17 Trost BM. Braslau R. J. Org. Chem.  1988,  53:  532 
• For examples, see:
• 21a Mello R. Fiorentino M. Fusco C. Curci R. J. Am. Chem. Soc.  1989,  111:  6749 
• 21b Davies HML. Manning JR. Nature  2008,  451:  417 
• 21c Fiori KW. Espino CG. Brodsky BH. Du Bois J. Tetrahedron  2009,  65:  3042 ; see also reference 4j
• For reports on Mn-catalyzed benzylic C-H oxidation, see:
• 23a Hamada T. Irie R. Hamachi K. Katsuki T. Tetrahedron  1998,  54:  10017 
• 23b Lee NH. Lee C.-S. Jung D.-S. Tetrahedron Lett.  1998,  39:  1385 
• 23c Havranek M. Singh A. Sames D. J. Am. Chem. Soc.  1999,  121:  8965 
• 23d Pan J.-F. Chen W. J. Mol. Catal. A: Chem.  2001,  176:  19 
• 23e Blay G. Fernández I. Giménez T. Pedro JR. Ruiz R. Pardo E. Lloret F. Muñoz MC. Chem. Commun.  2001,  2102 
• 23f Murahashi S.-I. Noji S. Hirabayashi T. Komiya N. Tetrahedron: Asymmetry  2005,  16:  3527 
• 23g Mardani HR. Golchoubian H. J. Mol. Catal. A: Chem.  2006,  259:  197 
• For recent examples of catalytic benzylic C-H oxidations, see:
• 24a Choudary BM. Prasad AD. Bhuma V. Swapna V. J. Org. Chem.  1992,  57:  5841 
• 24b Murahashi S.-I. Oda Y. Naota T. Kuwabara T. Tetrahedron Lett.  1993,  34:  1299 
• 24c Catino AJ. Nichols JM. Choi H. Gottipamula S. Doyle MP. Org. Lett.  2005,  7:  5167 
• 24d Bonvin Y. Callens E. Larrosa I. Henderson DA. Oldham J. Burton AJ. Barrett AGM. Org. Lett.  2005,  7:  4549 
• 24e Nakanishi M. Bolm C. Adv. Synth. Catal.  2007,  349:  861 
• 24f Nagano T. Kobayashi S. Chem. Lett.  2008,  37:  1042 
• 25a Walter DS. In Comprehensive Organic Functional Group Transformations   Vol. 3:  Katrizky AR. Meth-Cohn O. Rees CW. Pattenden G. Pergamon; Oxford: 1995.  p.293-294  
• 25b Larock RC. Comprehensive Organic Transformations: A Guide to Functional Group Preparations   2nd ed.:  Wiley-VCH; New York: 1999.  p.1205-1207  
• For examples of Mn-catalyzed oxidation of alcohols, see:
• 28a Berkessel A. Sklorz CA. Tetrahedron Lett.  1999,  40:  7965 
• 28b Brinksma J. Rispens MT. Hage R. Feringa BL. Inorg. Chim. Acta  2002,  337:  75 
• 28c Bagherzadeh M. Tetrahedron Lett.  2003,  44:  8943 
• 28d Bahramian B. Mirkhani V. Moghadam M. Amin AH. Appl. Catal., A  2006,  315:  52 
• 28e Mardani HR. Golchoubian H. Tetrahedron Lett.  2006,  47:  2349 
• 28f Rezaeifard A. Jafarpour M. Moghaddam GK. Amini F. Bioorg. Med. Chem.  2007,  15:  3097 
• 28g Romakh VB. Therrien B. Süss-Fink G. Shul’pin GB. Inorg. Chem.  2007,  46:  1315 
• 29 For the oxidation of alcohols by stoichiometric amounts of MnSO₄ and Oxone, see: Sánchez AV. Zárrage JG. J. Mex. Chem. Soc.  2007,  51:  213 
• 30 Travis BR. Ciaramitaro BP. Borhan B. Eur. J. Org. Chem.  2002,  3429 
• 33 Jõgi A. Paju A. Pehk T. Kailas T. Müürisepp A.-M. Kanger T. Lopp M. Synthesis  2006,  3031 

5

See reference 1b, pp 231-236 (MnO₂) and pp 311-317 (KMnO₄).

18

The addition of a small amount of water during preparation of the Mn catalyst helped to give reproducible results. Water dissolves the MnCl₂ salt and promotes the formation of the Mn catalyst.

19

Over-oxidation took place to produce cyclodocecane-1,5-dione as a byproduct (<5% yield).

20

See the experimental section for details.

22

Because methine C-H bonds have a higher intrinsic reactivity toward oxidation than do methylene C-H bonds, and no formation of octanoate ester was observed, we assumed that octanoic acid was generated through intermediate A; however, we cannot rule out the possibility of the involvement of intermediate B.

26

For pioneering works on benzylic C-H oxidation with a Mn/terpy catalyst and tetrabutylammonium Oxone (TBA-Oxone), see reference 14.

27

A stock solution of the premixed manganese complex in acetonitrile can be used.

31

The reaction in the absence of the Mn catalyst gave no oxidized product 2a, and quantitative recovery of alcohol 5a was observed. This result eliminates the possibility that dioxirane is formed from acetone under the reaction conditions.

32

Treatment of an olefin with the Mn catalyst/KHSO₅ system resulted in clean formation of an epoxide (Scheme  [6] ).

Scheme 6 Formation of an epoxide from an olefin