1,4-Reduction of α,β-Unsaturated Ketones through Rhodium(III)-Catalyzed Transfer Hydrogenation

Dedicated to Professor Masahiro Murakami on the occasion of his retirement from Kyoto University

Abstract

A rhodium(III)-catalyzed transfer hydrogenation of unsaturated ketones was developed. The simple catalytic system could be used for the 1,4-reduction of unsaturated cyclic, acyclic ketones, diketones, as well as β-ketoester, and a variety of functional groups were well-tolerated, affording products in moderate to excellent yields.

Key words

1,4-reduction - unsaturated ketone - rhodium(III) catalysis - transfer hydrogenation - isopropanol

Publication History

Received: 19 July 2022

Accepted after revision: 29 August 2022

Article published online:
30 September 2022

• References and Notes

• 1a Patai S, Rappoport Z. In The Chemistry of Enones . John Wiley & Sons; Chichester: 1989
• 1b Nashimura S. In Handbook of Heterogeneous Catalytic Hydrogenation for Organic Synthesis. Wiley-Interscience; New York: 2001
• 1c de Vries JG, Elsevier CJ. In The Handbook of Homogeneous Hydrogenation . Wiley-VCH; Weinheim: 2007
• 2a Farrar-Tobar RA, Dell'Acqua A, Tin S, de Vries JG. Green Chem. 2020; 22: 3323
• 2b Talwar D, Wu X, Saidi O, Salguero NP, Xiao J. Chem. Eur. J. 2014; 20: 12835 ; and references therein

For reviews, see:
• 3a Shi Z, Li N, Lu H.-K, Chen X, Zheng H, Yuan Y, Ye K.-Y. Curr. Opin. Electrochem. 2021; 28: 100713
• 3b Hollmann F, Opperman DJ, Paul CE. Angew. Chem. Int. Ed. 2021; 60: 5644
• 3c Lipshutz BH. Copper(I)-Mediated 1,2- and 1,4-Reductions. In Modern Organocopper Chemistry. Krause N. Wiley-VCH; Weinheim: 2002: 167

For a recent example, see:
• 3d Gu Y, Norton JR, Salahi F, Lisnyak VG, Zhou Z, Snyder SA. J. Am. Chem. Soc. 2021; 143: 9657
• 4a Baráth E. Catalysts 2018; 8: 671
• 4b Wang D, Astruc D. Chem. Rev. 2015; 115: 6621
• 5a Aboo AH, Bennett EL, Deeprose M, Robertson CM, Iggo JA, Xiao J. Chem. Commun. 2018; 54: 11805
• 5b Wu X, Li X, Zanotti-Gerosa A, Pettman A, Liu J, Mills AJ, Xiao J. Chem. Eur. J. 2008; 14: 2209
• 5c Murata K, Ikariya T, Noyori R. J. Org. Chem. 1999; 64: 2186
• 6 Manna S, Antonchick AP. ChemSusChem 2019; 12: 3094
• 7a Garg N, Sarkar A, Sundararaju B. Coord. Chem. Rev. 2021; 433: 213728
• 7b Trincado M, Banerjeea D, Grützmacher H. Energy Environ. Sci. 2014; 7: 2464
• 8 Aboo AH, Begum R, Zhao L, Farooqi ZH, Xiao J. Chin. J. Catal. 2019; 40: 1795

For examples on selective transfer hydrogenation of α,β-unsaturated ketones using isopropanol as hydrogen source, see:
• 9a Lator A, Gaillard S, Poater A, Renaud J.-L. Chem. Eur. J. 2018; 24: 5770
• 9b Gliński M, Ulkowska U. App. Catal., A 2018; 554: 117
• 9c Chen S.-j, Lu G.-p, Cai C. RSC Adv. 2015; 5: 13208
• 9d Mertens PG. N, Poelman H, Ye X, Vankelecom IF. J, Jacobs PA, De Vos DE. Catal. Today 2007; 122: 352
• 9e Braun F, Di Cosimo JI. Catal. Today 2006; 116: 206
• 9f Di Cosimo JI, Acosta A, Apesteguía CR. J. Mol. Catal. A: Chem. 2005; 234: 111
• 9g Mizushima E, Yamaguchi M, Yamagishi T. J. Mol. Catal. A: Chem. 1999; 148: 69
• 9h Bianchini C, Glendenning L, Zanobini F, Farnetti E, Graziani M, Nagy E. J. Mol. Catal. A: Chem. 1998; 132: 13
• 10 Crabtree RH. Chem. Rev. 2017; 117: 9228

For reviews on ruthenium-catalyzed transfer hydrogenation, see:
• 11a Ritleng V, de Vries JG. Molecules 2021; 26: 4076
• 11b Conley BL, Pennington-Boggio MK, Boz E, Williams TJ. Chem. Rev. 2010; 110: 2294
• 12 Carbonyl reduction of 1a and the subsequent condensation with isopropanol may deliver allylic isopropyl ether (Scheme 2). See: Sai M. Adv. Synth. Catal. 2018; 360: 3482
• 13 Typical Procedure To an oven-dried vial, 1-phenyl-3-(4-vinylphenyl)prop-2-en-1-one (1g′, 0.2 mmol, 46.9 mg), [(Cp*RhCl₂)₂] (0.006 mmol, 3.7 mg), and isopropanol (1.0 mL) were added. The vial was charged with N₂ and sealed immediately. The mixture was stirred at 100 °C for 12 h. After the completion of the reaction, the mixture was cooled down to room temperature, filtered through a Celite pad, and washed with ethyl acetate. The filtrate was concentrated in vacuo, and the residue was purified by column chromatography on silica gel (eluent: petroleum ether/ethyl acetate) to afforded 24.1 mg (51%) of 2g′ as an oil. ¹H NMR (CDCl₃, 400 MHz): δ = 7.97 (d, J = 5.6 Hz, 2 H), 7.56 (t, J = 5.8 Hz, 1 H), 7.48–7.44 (m, 2 H), 7.36 (d, J = 6.6 Hz, 2 H), 7.22 (d, J = 6.6 Hz, 2 H), 6.70 (dd, J = 14, 8.8 Hz, 1 H), 5.72 (d, J = 14 Hz, 1 H), 5.21 (d, J = 8.8 Hz, 1 H), 3.30 (t, J = 12.2 Hz, 2 H), 3.07 (t, J = 12.2 Hz, 2 H). ¹³C NMR (CDCl₃, 126 MHz): δ = 199.2, 140.9, 136.8, 136.5, 135.5, 133.1, 128.6, 128.0, 126.3, 113.2, 40.3, 29.8 ppm. IR (KBr): ν_max = 1680, 1630, 1600, 1579, 1508, 1448, 1206, 974, 742, 688 cm^–1. HRMS (ESI): m/z calcd for C₁₇H₁₆O⁺ [M + H]⁺: 237.1274; found: 237.1271.