A Sumanene-based Aryne, Sumanyne Niti Ngamsomprasert, Yumi Yakiyama, and Hidehiro Sakurai* Division of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Received December 8, 2016; CL-161117; E-mail: hsakurai@chem.eng.osaka-u.ac.jp) Copyright The Chemical Society of Japan
Contents 1. General information and preparations S1 2. Crystal structure of 3 S7 3. NMR Spectra S8 4. Computational data S22 5. Reference S24 1. General Information All chemicals were reagent grade and used as received if not mentioned. 1 H- and 13 C-NMR spectra were measured on a JEOL JNM-ECZS at 23 C at 400 and 100 MHz, respectively. A residual solvent peak was used as an internal standard ( 1 H-NMR: CDCl 3 7.24 ppm, CD 2 Cl 2 5.32 ppm; 13 C-NMR: CDCl 3 77.0 ppm, CD 2 Cl 2 53.8 ppm). High-resolution mass spectra (HRMS) were measured on a JEOL JMS-700 using fast atom bombardment (FAB) or electron impact (EI) mode. Gel permeable chromatography (GPC) was conducted on JAIGEL 1H and 2H using a JAI Recycling Preparative HPLC LC-908W with CHCl 3 as eluent. Biotage Initiator 2.0 was used for microwave conditions. Infrared (IR) spectra were recorded on a JASCO FT IR-4100 spectrometer. UV visible absorption spectra were recorded on a JASCO V-670 spectrometer. Fluorescence spectra were recorded on a JASCO FP6500 spectrometer. Melting points were determined on Standford Research Systems MPA 100 and were uncorrected. Merck pre-coated TLC plate (silica gel 60 F254 0.25 mm) was used for thin-layer chromatography (TLC) analysis. Preparative thin-layer chromatography (PTLC) was prepared using Wako Wakogel B-5F. The diffraction data for 3 precursor and 7d were recorded on a ADSC Q210 CCD area detector with a synchrotron radiation (λ= 0.70000 Å) at 2D beamline in Pohang Accelerator Laboratory (PAL) at 100 K in house. The diffraction images were processed by using HKL3000. 1 The structures were solved by direct methods (SHELXS) 2 and refined by full-matrix least squares calculations on F 2 (SHELXL) 3 using the Olex2 program package. 4 S1
o-hydroxysumanenyl pinocolatoborate (6) o-bromohydroxysumanene 5 5,6 (6.4 mg, 0.018 mmol), bis(pinocolato)diboron (13.6 mg, 0.054 mmol), [1,1 -bis(diphenylphosphino)ferrocene]dichloropalladium (3.9 mg, 5.3 µmol) and potassium acetate (1.8 mg, 0.018 mmol) were placed in a flask, and the mixture was evacuated and exchange to N 2 atmosphere for three times. Anhydrous toluene (1 ml) was added via syringe under atmospheric N 2 and the resulting solution was degassed twice by freeze-pump-thaw process, then was stirred at 90 C for 4 h. After let the reaction cooled down to room temperature, H 2 O 3 ml was added and the aqueous layer was extracted with CH 2 Cl 2 (5 mlx3). The combined organic layer was washed with brine and dried over Na 2 SO 4. After filtered through cotton and evaporated the organic solvent, the crude product was purified by GPC to give 6 as pale yellow oil (4.5 mg, 64% yield). 1 H NMR (CDCl 3 ): δ 8.38 (s, 1H), 7.12-6.98 (m, 4H), 4.72 (d, J = 20.4 Hz, 1H), 4.65 (d, J = 19.6 Hz, 1H), 4.58 (d, J = 20.8 Hz, 1H), 3.58 (d, J = 20.4 Hz, 1H), 3.54 (d, J = 20.4 Hz, 1H), 3.36 (d, J = 19.2 Hz, 1H), 1.33 (s, 6H), 1.32 (s, 6H); 13 C NMR (CDCl 3 ): 162.0, 159.9, 153.6, 149.3, 149.2, 149.19, 148.9, 148.89, 148.7, 148.6, 147.7, 147.2, 140.3, 129.3, 124.3, 123.4, 123.1, 121.9, 84.2, 84.19, 43.4, 41.6, 39.6, 25.0, 24.9, 24.65, 24.60 ppm; IR (KBr): υ 3410 (br), 2975, 1375, 1340, 1268, 1124, 1089, 965, 852, 707, 668, 645 cm 1 ; HRMS (FAB) m/z: Calcd. for C 27 H 23 BO 3 [M] + 406.1740, found 406.1732. (o-trifluoromethanesulfonyl)sumanenyl pinocolatoborate (3) S2
DBU (8.0 µl, 0.057 mmol) was added to a solution of 6 (4.6 mg, 0.011 mmol) and N-phenyl-bis(trifluoromethanesulfonimide) (12.1 mg, 0.034 mmol) in CH 2 Cl 2 (1 ml). The solution was stirred at room temperature for 15 min. After completion of the reaction, H 2 O (3 ml) was added and extracted with CH 2 Cl 2 (5 mlx3). The combined organic layer was washed with brine and dried over Na 2 SO 4. After filtered through cotton and evaporated the organic solvent, the crude product was purified by GPC to give 3 as pale yellow solid (3.7 mg, 61% yield). MP: 157.0 C (dec.); 1 H NMR (CDCl 3 ): δ 7.18-7.09 (m, 4H), 4.83 (d, J = 20.4 Hz, 1H), 4.71 (d, J = 19.6 Hz, 2H), 3.68 (d, J = 20.0 Hz, 1H), 3.66 (d, J = 20.8 Hz, 1H), 3.43 (d, J = 19.2 Hz, 1H); 13 C NMR (CDCl 3 ): 161.1, 150.8, 149.6, 149.5, 149.2, 149.1, 149.0, 148.2, 147.9, 147.8, 147.5, 146.6, 138.0, 124.9, 124.0, 123.4, 123.3, 84.1, 43.9, 41.8, 40.8, 25.0, 24.5 ppm; IR (KBr): υ 2985, 2912, 1464, 1377, 1194, 1146, 931, 852, 791, 700, 606 cm 1 ; HRMS (FAB) m/z: Calcd. for C 28 H 22 F 3 O 5 SB [M] + 538.1233, found 538.1226. General procedure for sumanyne formation CsF (300 mol%) was flame-dried under vacuum in a microwave tube and back-filled with nitrogen. 3 (100 mol%) and diene (1,000 mol%) in anhydrous MeCN (0.05 M) were added via syringe under nitrogen flow. The resulting solution was heated and stirred at 120 C under microwave irradiation for 2 h. After cooled down to room temperature, the reaction was diluted with CH 2 Cl 2 (3 ml) and quench with H 2 O (3 ml). The mixture was repeatedly extracted with CH 2 Cl 2 (3 mlx3). The combined organic phase was dried over Na 2 SO 4. After filtered through cotton and evaporated the solvent, the desired product was purified by PTLC or GPC. 8,11-Dimethyl-8,11-epoxybenzo[m]sumanene (7a) Following the general procedure, a microwave tube containing dried CsF (7.2 mg, 0.047 mmol), 3 (8.5 mg, 0.016 mmol) and 2,5-dimethylfuran (15.2 mg, 0.16 mmol) in anhydrous MeCN (310.0 µl, 0.05 M) was heated and stirred under microwave irradiation at 120 C for 2 h. The reaction mixture was purified by PTLC (CH 2 Cl 2 ) to S3
obtain 7a as yellow oil (5.7 mg, 53% yield, endo:exo = 1.2:1). 1 H NMR of endo 7a (CDCl 3 ): δ 7.12-7.05 (m, 4H), 6.98 (s, 2H), 4.72 (d, J = 19.2 Hz, 1H), 4.68 (s, J = 19.6 Hz, 2H), 3.72 (d, J = 18.4 Hz, 2H), 3.43 (d, J = 19.2 Hz, 1H), 1.91 (s, 3H); 1 H NMR of exo 7a (CDCl 3 ): δ 7.12-7.05 (m, 4H), 6.42 (s, 2H), 4.68 (s, J = 19.6 Hz, 1H), 4.63 (d, J = 19.6 Hz, 2H), 3.45 (d, J = 19.6 Hz, 1H), 3.37 (d, J = 19.2 Hz, 2H), 2.01 (s, 3H); 13 C NMR (CDCl 3 ): 148.9, 148.8, 148.7, 148.3, 148.2, 149.1, 147.4, 146.9, 146.8, 146.5, 146.1, 145.9, 145.3, 140.2, 138.5, 123.1, 123.0, 89.0 (endo C9=C10), 88.3 (exo C9=C10), 41.9 (exo CH 2 ), 41.7 (endo CH 2 ), 39.3 (endo CH 2 x2), 39.0 (exo CH 2 x2), 17.4 (exo CH 3 x2), 16.5 (endo CH 3 x2) ppm; IR (KBr): υ 3041, 2973, 2927, 2886, 1635, 1567, 1452, 1400, 1376, 1315, 1263, 1137, 1031, 856, 794, 727, 601 cm -1 ; HRMS (FAB) m/z: Calcd. for C 27 H 18 O [M] + 358.1358, found 358.1351. 8,11-Dihydro-8,11-epoxybenzo[m]sumanene (7b) Following the general procedure, a microwave tube containing dried CsF (7.1 mg, 0.047 mmol), 3 (8.4 mg, 0.016 mmol) and furan (10.6 mg, 0.15 mmol) in anhydrous MeCN (300.0 µl, 0.05 M) was heated and stirred under microwave irradiation at 120 C for 2 h. The reaction mixture was purified by PTLC (CH 2 Cl 2 ) to obtain 7b as pale yellow oil (2.0 mg, 40% yield; endo:exo = 2:1). 1 H NMR of endo 7b (CD 2 Cl 2 ): δ 7.19 (s, 2H), 7.14-7.07 (m, 4H), 5.61 (s, 2H), 4.70 (d, J = 20.0 Hz, 1H), 4.62 (d, J = 18.4 Hz, 2H), 3.58 (d, J = 19.2 Hz, 2H), 3.47 (d, J = 19.6 Hz, 1H), 1 H NMR of exo 7b (CD 2 Cl 2 ): δ 7.14-7.07 (m, 4H), 6.66 (s, 2H), 5.80 (s, 2H), 4.71 (d, J = 20.3 Hz, 1H), 4.67 (d, J = 16.4 Hz, 2H), 3.47 (d, J = 19.6 Hz, 1H), 3.36 (d, J = 19.2 Hz, 2H); 13 C NMR (CDCl 3 ):151.0, 149.4, 149.2, 148.8, 148.7, 148.6, 148.0, 147.4, 146.6, 146.5, 144.2, 143.7, 143.1, 142.7, 141.6, 140.3, 123.6 (exo C9=C10), 123.47 (endo C9=C10), 123.45, 80.9, 42.0 (exo CH 2 x1), 41.9 (endo CH 2 x1), 39.9 (endo CH 2 x2), 39.6 (exo CH 2 x2) ppm; IR (KBr): υ 2999, 2883, 1398, 1375, 1282, 1019, 872, 829, 787 cm 1 ; HRMS (FAB) m/z: Calcd. for C 25 H 14 O [M] + 330.1045, found 330.1049. 2,3,4,5-Tetraphenylbenzo[c]sumanene (7c) S4
Following the general procedure, a microwave tube containing dried CsF (6.4 mg, 0.042 mmol), 3 (7.6 mg, 0.014 mmol) and tetraphenylcyclopentadienone (54.3 mg, 0.14 mmol) in anhydrous MeCN (280.0 µl, 0.05 M) was heated and stirred under microwave irradiation at 120 C for 2 h. The reaction mixture was purified by PTLC (20% EtOAc/Hexane) to obtain 7c (3.1 mg, 36% yield). MP: 154.0 o C (dec.); 1 H NMR (CD 2 Cl 2 ): δ 7.57 (d, J = 7.6 Hz, 2H), 7.43 (t, J = 7.6 Hz, 2H), 7.27 (t, J = 7.2 Hz, 2H), 7.18 (d, J = 7.6 Hz, 2H), 7.17 (t, J = 6.8 Hz, 2H), 7.09 (d, J = 8.4 Hz, 2H), 7.07 (d, J = 7.6 Hz, 2H), 6.92 (t, J = 7.2 Hz, 2H), 6.89 (d, J = 8.0 Hz, 2H), 6.83 (t, J = 7.6 Hz, 2H), 6.78 (t, J = 7.6 Hz, 2H), 6.71 (d, J = 7.2 Hz, 2H), 4.61 (d, J = 20.4 Hz, 1H), 3.59 (d, J = 20.8 Hz, 2H), 3.33 (d, J = 19.6 Hz, 1H), 2.83 (d, J = 20.8 Hz, 2H); 13 C NMR (CD 2 Cl 2 ): 149.2, 148.6, 147.4, 147.2, 146.3, 145.2, 142.9, 141.0, 139.2, 133.2, 132.5, 132.1, 131.6, 131.0, 128.3, 127.6, 126.9, 126.4, 125.5, 124.2, 123.3, 44.4, 41.9 ppm; IR (KBr): υ 3049, 3024, 2924, 2852, 1442, 1400, 1263, 1095, 1068, 1031, 795, 769, 700 cm 1 ; HRMS (EI) m/z: Calcd. for C 49 H 30 [M] + 618.2348, found 618.2348. 8,13-Dihydro-8,13-benzonaphtho[2,3-m]sumanene (7d) Following the general procedure, a microwave tube containing dried CsF (5.6 mg, 0.037 mmol), 3 (6.6 mg, 0.012 mmol) and anthracene (43.7 mg, 0.12 mmol) in anhydrous MeCN (200.0 µl, 0.05 M) was heated and stirred under microwave irradiation at 120 C for 2 h. The reaction mixture was purified by GPC (CHCl 3 ) to obtain 7d as yellow solid (0.9 mg, 17% yield). MP: 152.0 o C (dec.); 1 H NMR (CDCl 3 ): δ 7.51 (dd, J = 5.2, 3.2 Hz, 2H), 7.18 (dd, J = 5.2, 3.2 Hz, 2H),7.10 (dd, J = 5.6, 3.2 Hz, 2H), 7.11 (s, 4H), 6.78 (dd, J = 5.6, 3.2 Hz, 2H), 5.52 (s, 2H), 4.76 (d, J = 19.2 Hz 2H), 4.63 (d, J = 19.6 Hz, 1H), 3.52 (d, J = 19.6 Hz, 2H), 3.36 (d, J = 20.0 Hz, 1H); 13 C NMR (CDCl 3 ): 148.9, S5
148.8, 148.5, 147.8, 146.1, 144.7, 144.5, 143.3, 140.5, 125.5, 125.0, 123.9, 123.2, 123.1, 122.9, 51.8, 41.6, 39.7 ppm; IR (KBr): υ 30.41, 3012, 2954, 2923, 2886, 1635, 1459, 1376, 1216, 1186, 1168, 786, 757, 590 cm 1 ; HRMS (FAB) m/z: Calcd. for C 35 H 20 [M] + 440.1565, found 440.1568. 8-Hydroxybenzo[2,3-m]sumanene (8) A solution of 7b (2.1, 6.4 µmol) in 1 ml of 5% HCl/THF was stirred at 85 C for 4 h under N 2 atmosphere. After completion of the reaction, reaction mixture was neutralized by saturated NaHCO 3 and extracted with CH 2 Cl 2 (5 mlx3). The combined organic layer was washed with brine and dried over Na 2 SO 4. After filtered through cotton and evaporated the organic solvent, the crude product was purified by PTLC (CH 2 Cl 2 ) to give 8 as brown solid (1.4 mg, 67% yield). MP: 112.0 C (dec.); 1 H NMR (CDCl 3 ): δ 7.57 (d, J = 8.0 Hz, 1H), 7.31 (dd, J = 8.0, 7.2 Hz, 1H), 7.18-7.11 (m, 4H), 6.82 (d, J = 7.2 Hz, 1H), 5.63 (s, 1H), 5.07 (d, J = 21.2 Hz, 1H), 4.94 (d, J = 20.4 Hz, 1H), 4.67 (d, J = 19.6 Hz, 1H), 3.89 (d, J = 21.6 Hz, 1H), 3.61 (d, J = 20.0 Hz, 1H), 3.38 (d, J = 19.6 Hz, 1H); 13 C NMR (CDCl 3 ): 153.7, 150.4, 149.8, 149.0, 148.8, 148.51, 148.50, 147.9, 147.4, 146.2, 145.6, 145.0, 144.5, 134.4, 125.8, 124.2, 124.1, 124.0, 123.99, 123.9, 119.0, 108.7, 44.9, 42.1, 41.9 ppm; IR (KBr): υ 3384 (br), 2928, 2856, 1521, 1461, 1396, 1263, 803, 784, 666 cm 1 ; HRMS (FAB) m/z: Calcd. for C 25 H 14 O [M] + 330.1045, found 330.1048. S6
2. Crystal structure of 3 Figure S1. (a) ORTEP drawing of 3 with 50% probability. (b) Bowl depth of 3 measured from the plane of bottom benzene ring to the plane composed from six rim carbons. (c) Packing structure viewed along b axis. (d) Distance between the packing layers measured between planes of bottom benzene of the neighboring layer (viewed along c axis). (e) Space filling model showing bidirection packing structure of 3 along a axis. S7