Supporting Information

Supporting Information Rhodium-catalyzed Intramolecular Dehydrogenative Aryl Aryl Coupling Using Air as Terminal Oxidant Hannah Baars, 1,2 Yuto Unoh, 1 Takeshi Okada, 1 Koji Hirano, 1 Tetsuya Satoh,* 1,3 Ken Tanaka, 3,4 Carsten Bolm, 2 and Masahiro Miura* 1 1 Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 2 Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany 3 ACT-C, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 4 Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8550 (Received July 19, 2014; CL-140690; E-mail: satoh@chem.eng.osaka-u.ac.jp) Copyright The Chemical Society of Japan

Supporting Information Experimental Section General. 1 H and 13 C NMR spectra were recorded at 400 and 100 MHz for CDCl 3 solutions. MS data were obtained by EI. GC analysis was carried out using a silicon OV-17 column (i. d. 2.6 mm x 1.5 m). GC-MS analysis was carried out using a CBP-1 capillary column (i. d. 0.25 mm x 25 m). 1-Amino-1,1-diphenylalkanes 1b-e, S1 triarylmethanamines 1f-j, S2,S3 2,2-di-4-tolylpropanoic acid 3b, S4 and [Cp E RhCl 2 ] 2 11 were prepared according to published procedure. Other reagents were commercially available. (4-Chlorophenyl)-di-(4-methylphenyl)-methanamine (1i): mp: 97-98 C; column chromatography eluent: hexaneethyl acetate (3:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 2.21 (s, 2H), 2.32 (s, 6H), 7.06-7.13 (m, 8H), 7.18-7.25 (m, 4H); 13 C NMR (100 MHz, CDCl 3 ) δ 21.0, 65.5, 127.9 (overlapped), 128.7, 129.6, 132.4, 136.4, 145.5, 147.5. General Procedure for Cyclization of 1-Amino-1,1-diarylalkanes. To a 20 ml two-necked flask with a reflux condenser, a drying tube filled with CaCl 2, and a rubber cup were added amine 1 (0.5 mmol), [RhCl(cod)] 2 (0.01 mmol, 5.0 mg), Cu(OAc) 2 H 2 O (0.1 mmol, 20 mg), pivalic acid (0.5 mmol, 51 mg), dibenzyl (ca. 50 mg) as internal standard, and diglyme (3 ml). Then, the resulting mixture was stirred under air 150 o C (bath temperature) for 1-2 h. After cooling, to the reaction mixture was added water (30 ml) and ethylenediamine (2 ml). The mixture was extracted with ethyl acetate (3x30 ml) and dried over Na 2 SO 4. After evaporation of the solvents under vacuum, product 2 was isolated by column chromatography using eluent shown below. General Procedure for Cyclization of 2,2-Diarylpropanoic Acid. To a 20 ml two-necked flask with a reflux condenser, a drying tube filled with CaCl 2, and a rubber cup were added 2,2-diarylpropanoic acid 3 (0.5 mmol), [Cp*Rh(MeCN) 3 ][SbF 6 ] 2 (0.02 mmol, 16.6 mg), Cu(OAc) 2 H 2 O (0.02 mmol, 4.5 mg), K 2 CO 3 (0.25 mmol. 35 mg), pivalic acid (0.5 mmol, 51 mg), 1-methylnaphthalene (ca. 50 mg) as internal standard, and diglyme (3 ml). Then, the resulting mixture was stirred under air at 120 o C (bath temperature) for 12 h. After cooling, to the reaction mixture were added water (20 ml), ethyl acetate (20 ml) and ethylenediamine (2 ml) and filtered through celite plug. The filtrate was extracted with ethyl acetate (20x3 ml) and dried over Na 2 SO 4. After evaporation of the solvents under vacuum, the product 4 was isolated by column chromatography on silica gel using n-hexane as eluent. General Procedure for Cyclization of Diphenylacetic Acid. To a 20 ml two-necked flask with a reflux condenser, a drying tube filled with CaCl 2, and a rubber cup were added diphenylacetic acid 3c (0.5 mmol), [Cp E RhCl 2 ] 2 (0.01 mmol, 8.4 mg), AgSbF 6 (0.04 mmol, 13.7 mg), Cu(OAc) 2 H 2 O (0.02 mmol, 4.5 mg), K 2 CO 3 (0.25 mmol. 35 mg), pivalic acid (0.5 mmol, 51 mg), 1-methylnaphthalene (ca. 50 mg) as internal standard, and diglyme (3 ml). Then, the resulting mixture was stirred under air at 120 o C (bath temperature) for 48 h. After cooling, to the reaction mixture were added water (20 ml), ethyl acetate (20 ml) and ethylenediamine (2 ml) and filtered through celite plug. The filtrate was extracted with ethyl acetate (20x3 ml) and dried over Na 2 SO 4. After evaporation of the solvents under vacuum, the product 5 was isolated by column chromatography on silica gel using n-hexane/ethyl acetate (10:1) as eluent. Characterization Data of Products. 9-Phenyl-9H-fluoren-9-amine (2a): 4 oil, 107 mg (83%); column chromatography eluent: hexane-ethyl acetate (2:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 2.01 (s, 2H), 7.18-7.27 (m, 5H), 7.28-7.32 (m, 2H), 7.34 (td, J = 1.4, 7.4 Hz, 2H), 7.38-7.42 (m, 2H), 7.70 (d, J = 7.5 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 68.3, 120.2, 124.3, 126. 0, 127.1, 128.3, 128.4 (overlapped), 139.5, 144.7, 153.2; HRMS m/z calcd for C 19 H 15 N (M + ) 257.1204, found 257.1203. 9-Methyl-9H-fluoren-9-amine (2b): 4 oil, 65 mg (66%); column chromatography eluent: ethyl acetate; 1 H NMR (400 MHz, CDCl 3 ) δ 1.63 (s, 3H), 1.72 (s, 2H), 7.29-7.38 (m, 4H), 7.49-7.55 (m, 2H), 7.64-7.69 (m, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 28.0, 62.3, 120.2, 122.8, 128.0, 128.1, 138.8, 152.6; HRMS m/z calcd for C 14 H 13 N (M + ) 195.1048, found 195.1049. 9-Propyl-9H-fluoren-9-amine (2c): 4 oil, 83 mg(74%); column chromatography eluent: ethyl acetate; 1 H NMR (400 MHz, CDCl 3 ) δ 0.71 (t, J = 7.1 Hz, 3H), 0.75-0.86 (m, 2H), 1.73 (s, 2H), 1.98-2.06 (m, 2H), 7.28-7.37 (m, 4H), 7.44-7.49 (m, 2H), 7.62-7.68 (m, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 14.3, 17.6, 43.6, 65.5, 119.9, 122.9, 127.7, 127.9, 139.6, 151.2; HRMS m/z calcd for C 16 H 17 N (M + ) 223.1361, found 223.1359. 9-(i-Propyl)-9H-fluoren-9-amine (2d): 4 oil, 85 mg (76%); column chromatography eluent: ethyl acetate; 1 H NMR (400 MHz, CDCl 3 ) δ 0.78 (d, J = 6.8 Hz, 6H), 1.74 (s, 2H), 2.36 (sept, J = 6.8 Hz, 1H), 7.29 (td, J = 1.3, 7.4 Hz, 2H), 7.34 (td, J = 1.3, 7.4 Hz, 2H), 7.48 (dd, J = 1.2, 7.2 Hz, 2H), 7.65 (dd, J = 1.2, 7.5 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 17.5, 37.9, 68.3, 119.7, 123.5, 127.4, 127.9, 140.1, 150.6; HRMS m/z calcd for C 16 H 17 N (M + ) 223.1361, found 223.1360. Mixture of 2 isomers: 12-Methyl-12H-dibenzo[b,h]fluoren-12-amine (2e) / 7-methyl-7H-dibenzo[b,g]fluoren-7- amine (2e )= 3/1: 4 mp: 79-81 C, 80 mg (54%); column chromatography eluent: ethyl acetate; major isomer: 1 H NMR (400 MHz, CDCl 3 ) δ 1.80 (s, 3H), 2.00 (brs, 2H), 7.44-7.52 (m, 4H), 7.85-8.00 (m, 6H), 8.23 (s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 29.8, 61.5, 119.0, 121.7, 125.96, 126.04, 128.27, 128.32, 134.0, 134.1, 136.9, 151.0; HRMS m/z calcd for C 22 H 17 N (M + ) 295.1261, found 295.1362; minor isomer: 1 H NMR (400 MHz, CDCl 3 ) δ 1.75 (s, 3H), 2.00 (brs, 2H), 7.43-7.59 (m, 3H), 7.69-7.73 (m, 2H), 7.85-8.00 (m, 5H), 8.64 (s, 1H), 8.87 (d, J = 8.4 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 28.4, 61.5, 120.9, 121.1, 124.2, 125.7, 126.0, 127.2, 127.9, 128.6, 129.4, 129.7, 129.9, 132.4, 132.8, 134.3, 138.5, 5xC q not detected. 1

3,6-Dimethyl-9-(4-methylphenyl)-9H-fluoren-9-amine (2f): 4 oil, 134 mg (89%); column chromatography eluent: hexane-ethyl acetate (3:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 1.95 (s, 2H), 2.27 (s, 3H), 2.41 (s, 6H), 7.04 (t, J = 7.8 Hz, 4H), 7.17 (d, J = 7.7 Hz, 2H), 7.27 (d, J = 8.2 Hz, 2H), 7.48 (s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 21.0, 21.5, 67.4, 120.5, 123.8, 125.8, 128.9 (overlapped), 136.3, 137.8, 139.5, 142.0, 150.9; HRMS m/z calcd for C 22 H 21 N (M + ) 299.1674, found 299.1672. 3,6-Difluoro-9-(4-fluorophenyl)-9H-fluoren-9-amine (2g): mp: 86-88 C, 129 mg (83%); column chromatography eluent: hexane-ethyl acetate (1:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 1.99 (s, 2H), 6.90-7.00 (m, 4H), 7.22 (dd, J = 5.0, 8.3 Hz, 2H), 7.29-7.38 (m, 4H); 13 C NMR (100 MHz, CDCl 3 ) δ 67.0, 107.5 (d, J = 23 Hz), 115.2 (d, J = 21 Hz), 115.7 (d, J = 23 Hz), 125.5 (d, J = 9 Hz), 127.5 (d, J = 8 Hz), 139.7 (d, J = 3 Hz), 140.3 (dd, J = 3, 9 Hz), 149.1 (d, J = 2 Hz), 162.1 (d, J = 246 Hz), 163.3 (d, J = 246 Hz); HRMS m/z calcd for C 19 H 12 NF 3 (M + ) 311.0922, found 311.0920. 3,6-Dichloro-9-(4-chlorophenyl)-9H-fluoren-9-amine (2h): mp: 116-117 C, 120 mg (67%); column chromatography eluent: hexane-ethyl acetate (2:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 1.96 (s, 2H), 7.16-7.23 (m, 4H), 7.24 (d, J = 1.9 Hz, 1H), 7.25-7.27 (m, 1H), 7.30 (dt, J = 2.3, 8.7 Hz, 2H), 7.63 (d, J = 1.9 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 67.3, 120.7, 125.4, 127.3, 128.6, 128.9, 133.3, 134.6, 139.8, 142.1, 151.2; HRMS m/z calcd for C 19 H 12 NCl 3 (M + ) 359.0035, found 359.0038. 3-Chloro-6-methyl-9-(4-methylphenyl)-9H-fluoren-9-amine (2i) / 9-(4-chlorophenyl)-3,6-dimethyl-9H-fluoren-9- amine (2i ) = 7/1: oil, 113 mg (71%); column chromatography eluent: hexane-ethyl acetate (2:1, v/v); major isomer: 1 H NMR (400 MHz, CDCl 3 ) δ 1.93 (s, 2H), 2.28 (s, 3H), 2.42 (s, 3H), 7.04 (d, J = 8.1 Hz, 2H), 7.08-7.11 (m, 1H), 7.15-7.20 (m, 3H), 7.22 (s, 1H), 7.26-7.28 (m, 1H), 7.47 (s, 1H), 7.62 (s, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 21.0, 21.5, 67.5, 120.2, 120.9, 124.0, 125.3, 125.7, 127.4, 127.9, 128.3, 129.1, 129.8, 134.0, 136.7, 138.2, 141.2, 150.8, 151.8; HRMS m/z calcd for C 21 H 18 NCl (M + ) 319.1128, found 319.1129; minor isomer: 1 H NMR (400 MHz, CDCl 3 ) δ 1.93 (s, 2H), 2.42 (s, 6H), 7.07 (s, 1H), 7.13 (d, J = 7.7 Hz, 2H), 7.22 (d, J = 4.2 Hz, 1H), 7.33 (d, J = 8.6 Hz, 2H), 7.49 (s, 2H), 7.53 (dd, J = 3.4, 5.7 Hz, 1H), 7.71 (dd, J = 3.3, 5.7 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 21.6, 120.7, 123.7, 127.9, 128.7, 129.0, 6xC q not detected. 1-Methyl-9-phenyl-9H-fluoren-9-amine (2j): mp: 138-140 C, 54 mg (40%); column chromatography eluent: hexaneethyl acetate (20:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 1.20 (s, 3H), 1.92 (s, 2H), 6.92 (d, J = 7.4 Hz, 1H), 7.11 (dt, J = 0.8, 7.6 Hz, 2H), 7.17-7.24 (m, 3H), 7.32-7.39 (m, 3H), 7.72 (dt, J = 0.8, 7.5 Hz, 2H), 8.36 (dd, J = 1.2, 7.9 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 19.6, 67.6, 120.3, 123.5, 125.7, 126.9, 127.4, 128.1, 128.4, 131.7, 136.3, 139.9, 141.0, 152.1; HRMS m/z calcd for C 20 H 17 N (M + ) 271.1361, found 271.1359. 9-(4-Methylphenyl)-9H-fluoren-9-amine (2j ): oil, 55 mg (40%); column chromatography eluent: hexane-ethyl acetate (20:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 2.02-2.11 (m, 5H), 7.02 (d, J = 7.5 Hz, 1H), 7.16-7.21 (m, 3H), 7.21-7.25 (m, 2H), 7.26-7.30 (m, 2H), 7.34-7.39 (m, 2H), 7.58 (d, J = 7.6 Hz, 1H), 7.66 (dt, J = 0.8, 7.6 Hz, 1H); 13 C NMR (100 MHz, CDCl 3 ) δ 18.1, 68.6, 117.7, 120.0, 123.8, 125.7, 126.7, 128.0, 128.2, 128.3, 128.5, 130.4, 134.9, 138.9, 140.2, 143.5, 150.0, 153.7; HRMS m/z calcd for C 20 H 17 N (M + ) 271.1361, found 271.1362. 9-Methyl-9H-fluorene (4a): 4 mp 42-44 C, 75 mg (84%); column chromatography eluent: hexane; 1 H NMR (400 MHz, CDCl 3 ) δ 1.53 (d, J = 7.4 Hz, 3H), 3.95 (q, J = 7.4 Hz, 1H), 7.30-7.38 (m, 4H), 7.50 (d, J = 7.2 Hz, 2H), 7.76 (d, J = 7.0 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 18.3, 42.6, 120.0, 124.2, 127.06, 127.08, 140.7, 149.1; HRMS m/z calcd for C 14 H 12 (M + ) 180.0939, found 180.0936. 3,6,9-trimethyl-9H-fluorene (4b): mp 62-63 C, 86 mg (83%); column chromatography eluent: hexane; 1 H NMR (400 MHz, CDCl 3 ) δ 1.47 (d, J = 7.4 Hz, 3H), 2.44 (s, 6H), 3.86 (q, J = 7.4 Hz, 1H), 7.12 (d, J = 7.6 Hz, 2H), 7.37 (d, J = 7.6 Hz, 2H), 7.55 (s, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 18.6, 21.7, 41.9, 120.5, 123.8, 127.8, 136.6, 140.8, 146.8; HRMS m/z calcd for C 16 H 16 (M + ) 208.1252, found 208.1251. 9H-fluoren-9-one (5): S5 mp 81-82 C, 27 mg (30%); column chromatography eluent: hexane-ethyl acetate (10:1, v/v); 1 H NMR (400 MHz, CDCl 3 ) δ 7.30 (dt, J = 1.2, 7.3 Hz, 2H), 7.49 (dt, J = 1.2, 7.3 Hz, 2H), 7.51-7.54 (m, 2H), 7.66 (d, J = 6.9 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ) δ 120.5, 124.5, 129.2, 134.3, 134.8, 144.6, 194.1; HRMS m/z calcd for C 13 H 8 O (M + ) 180.0575, found 180.0572. References 4 K. Morimoto, M. Itoh, K. Hirano, T. Satoh, Y. Shibata, K. Tanaka, M. Miura, Angew. Chem. Int. Ed. 2012, 51, 5359. 11 Y. Shibata, K. Tanaka, Angew. Chem. Int. Ed. 2011, 50, 10917. S1 O. A. Tomashenko, V. V. Sokolov, A. A. Tomashevskii, A. A. Potekhin, A. Meijere, Russ. J. Org. Chem. 2007, 43, 1421. S2 L. Buesetto, M. C. Cassani, C. Femoni, M. Mancinelli, A. Mazzanti, R. Mazzoni, G. Solinas, Organometallics 2011, 30, 5258. S3 V. Theodorou, K. Skobridis, A. Karkatsoulis, Tetrahedron 2007, 63, 4284. S4 B.-F. Shi, Y.-H. Zhang, J. K. Lam, D.-H. Wang, J.-Q. Yu, J. Am. Chem. Soc. 2010, 132, 460. S5 M. Miura, M. Nojima, S. Musabayashi, J. Chem. Soc. Perkin 1 1980, 1950. 2

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