Highly Selective Reductive Cross-Amination between Aniline or Nitroarene Derivatives and Alkylamines Catalyzed by Polysilane-Immobilized Rh/Pt Bimetallic NanoparticlesThis work was partially supported by a Grant-in-Aid for Science Research from the Japan Society for the Promotion of Science (JSPS), the Global COE Program, The University of Tokyo, Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan, and the Japan Science and Technology Agency (JST). A. S. thanks the JSPS fellowship for Japanese Junior Scientist.
Accepted after revision: 17 October 2018
18 January 2019 (online)
Published as part of the 30 Years SYNLETT – Pearl Anniversary Issue
Reductive cross-amination between imine intermediates generated through partial hydrogenation of aniline or nitroarene derivatives and alkylamines is an ideal method for obtaining N-alkylated cyclohexylamine derivatives; however, no such transformations have hitherto been established. Here, we report a highly selective reductive cross-amination using aniline derivatives and alkylamines catalyzed by heterogeneous Rh/Pt bimetallic nanoparticles under mild conditions. The catalyst was recovered and reused for five runs, keeping high activity. In this reaction, imine intermediates generated during the course of partial hydrogenation of aniline derivatives were trapped immediately by strongly interacting primary alkylamines with the catalyst, which caused a highly selective transformation to give the desired products, while suppressing dicyclohexylamine formation.
References and Notes
- 1 Ding K, Uozumi Y. Handbook of Asymmetric Heterogeneous Catalysis . Wiley-VCH; Weinheim: 2008
- 2 Kobayashi S, Miyamura H. Aldrichimica Acta 2013; 46: 17
- 3 Miyamura H, Kobayashi S. Acc. Chem. Res. 2014; 47: 1054
- 4a Yasukawa T, Suzuki A, Miyamura H, Nishino K, Kobayashi S. J. Am. Chem. Soc. 2015; 137: 6616
- 4b Miyamura H, Suzuki A, Yasukawa T, Kobayashi S. Adv. Synth. Catal. 2015; 357: 3815
- 5 Miyamura H, Suzuki A, Yasukawa T, Kobayashi S. J. Am. Chem. Soc. 2018; 140: 11325
- 6a Nugent TC. Chiral Amine Synthesis: Methods, Developments and Applications. Wiley; Hoboken: 2010
- 6b Ricci A. Modern Amination Methods . Wiley; Hoboken: 2008
- 6c Breuer M, Ditrich K, Habicher T, Hauer B, Keßeler M, Stürmer R, Zelinski T. Angew. Chem. Int. Ed. 2004; 43: 788
- 7a Yin Z, Zeng H, Wu J, Zheng S, Zhang G. ACS Catal. 2016; 6: 6546
- 7b Kim I, Itagaki S, Jin X, Yamaguchi K, Mizuno N. Catal. Sci. Technol. 2013; 3: 2397
- 7c Lorentz-Petersen LL. R, Jensen P, Madsen R. Synthesis 2009; 4110
- 7d Hollmann D, Bahn S, Tillack A, Beller M. Chem. Commun. 2008; 3199
- 7e Hollmann D, Bähn S, Tillack A, Beller M. Angew. Chem. Int. Ed. 2007; 46: 8291
- 7f Tillack A, Hollmann D, Michalik D, Beller M. Tetrahedron Lett. 2006; 47: 8881
- 8a Song W.-H, Liu M.-M, Zhong D.-W, Zhu Y.-l, Bosscher M, Zhou L, Ye D.-Y, Yuan Z.-H. Bioorg. Med. Chem. Lett. 2013; 23: 4528
- 8b Chen T, Takrouri K, Hee-Hwang S, Rana S, Yefidoff-Freedman R, Halperin J, Natarajan A, Morisseau C, Hammock B, Chorev M, Aktas BH. J. Med. Chem. 2013; 56: 9457
- 9a Jumde VR, Petricci E, Petrucci C, Santillo N, Taddei M, Vaccaro L. Org. Lett. 2015; 17: 3990
- 9b Chen Z, Zeng H, Gong H, Wang H, Li C.-J. Chem. Sci. 2015; 6: 4174
- 9c Chen Z, Zeng H, Girard SA, Wang F, Chen N, Li C.-J. Angew. Chem. Int. Ed. 2015; 54: 14487
- 9d Li J.-S, Qiu Z, Li C.-J. Adv. Synth. Catal. 2017; 359: 3648
- 10 Rubio-Marques P, Leyva-Perez A, Corma A. Chem. Commun. 2013; 8160
- 11 Rh-Pt/(DMPSi-Al2O3) (33.4 mg, 0.75 mol% as Rh), n-octylamine (1a) (51.7 mg, 0.4 mmol) and aniline (2a) (74.0 mg, 0.8 mmol) were placed in a Caroucel® tube. The atmosphere was exchanged to H2 using a balloon and pump. The reaction mixture was stirred at 50 °C for 24 h, then the reaction was quenched by the addition of EtOAc (5 mL) and the reaction mixture was analyzed by GC using decane as internal standard. Yield: 93%; GC flow rate (157.5 kPa, He), Inject (50 °C), Detect (100 °C), Int. T (50 °C), Int. T (0 min), Rate (5 °C/min), Fin. T (100 °C), Fin. T (10 min): tR = 30.068 (N-n-octylcyclohexylamine), 19.304 (decane internal standard) min.
- 12 Rh-Pt/(DMPSi-Al2O3) (81.2 mg, 0.75 mol% as Rh), 3-methoxypropylamine (1d) (176.7 mg, 1.2 mmol) and aniline (2a) (279.4 mg, 3.0 mmol) were placed in a Caroucel® tube. The atmosphere was exchanged to H2 using balloon and pump. After the reaction mixture was stirred at 50 °C for 38 h, the reaction was quenched by the addition of CH2Cl2 (5 mL). The catalyst was filtered off and the filtrate was concentrated. The desired product was isolated from the crude mixture by column chromatography (hexane/EtOAc/Et3N = 3:2:0.1). Yield: 97%; 1H NMR (600 MHz, CDCl3): δ = 3.44 (t, J = 6.2 Hz, 2 H), 3.32 (s, 3 H), 2.71 (t, J = 6.9 Hz, 2 H), 2.44–2.39 (m, 1 H), 1.87 (d, J = 13.0 Hz, 2 H), 1.77–1.70 (m, 4 H), 1.63–1.59 (m, 1 H), 1.42 (br, 1 H), 1.29–1.21 (m, 2 H), 1.19–1.14 (m, 1 H), 1.09–1.03 (m, 2 H). 13C NMR (100 MHz, CDCl3): δ = 71.4, 58.6, 56.9, 44.3, 33.6, 30.4, 26.2, 25.1. IR (neat): 3579, 3312, 2928, 2853, 1672, 1454, 1375, 1304, 1255, 1195 cm–1. HRMS (DART): m/z [M+H]+ calcd for C10H22NO+: 172.17014; found: 172.16781.