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1 DOI: /NCHEM.2417 Conversion of alkanes to linear alkylsilanes using an iridium-iron-catalysed tandem dehydrogenation-isomerisation-hydrosilylation Xiangqing Jia 1 and Zheng Huang 1 * 1 State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai , China * huangzh@sioc.ac.cn This PDF file includes: Materials and Methods Supplementary Table S1 Supplementary Table S2 References NMR Spectra Table of Contents: 1. General Information a. Materials....2 b. Analytical methods Procedures for Table Table S1 Evaluation of metal catalysts for tandem olefin isomerisation-hydrosilylation Table S2 Evaluation of the relative rates for isomerisation-hydrosilylation of 1-, 2-, or 3-octenes Procedures for Table Procedures for Table General procedures for preparation of the standard alkylboronates References NMR spectra for isolated compounds NATURE CHEMISTRY 1

2 1. General information a. Materials All manipulations were carried out using standard Schlenk, high-vacuum and glovebox techniques. Toluene and p-xylene were dried with Na and distilled under argon. n-hexane was dried with CaH 2 and distilled under argon. Alkanes were dried with Na, vacuum transferred, and stored under argon. t-butylethylene (TBE) was purchased from TCI, and dried with LiAlH 4, vacuum transferred, and stored under argon. (Me 3 SiO) 2 MeSiH (MD M) and Et 2 SiH 2 were purchased from TCI. Both silanes were dried with CaH 2, and distilled under argon. Pinacolborane (HBPin) was purchased from TCI and purified according to the reported procedure 1. Other reagents were purchased from commercial suppliers and used without further purification. (PSCOP)IrHCl (1) 2, (PNN)FeCl 2 (2a) 3, ( ipr PDI)FeBr 2 (2b) 4, ( Et PDI)FeBr 2 (2c) 5 and ( Me PDI)FeBr 2 (2d) 4 were prepared as previously reported. b. Analytical methods NMR spectra were recorded on Varian 300 or 400 MHz spectrometers and Agilent 400 MHz spectrometers at ambient temperature. The residual peak of deuterated solvent was used as a reference for 1 H and 13 C chemical shifts. GC analysis was acquired on Agilent 7820A gas chromatograph equipped with a flame-ionization detector. GC-MS analysis was performed on Agilent 7890A gas chromatograph coupled to an Agilent 5975C inert mass selective detector. High resolution mass spectrometer (HRMS) was performed by the Analytical Laboratory of Shanghai Institute of Organic Chemistry (CAS). 2. Procedures for Table 1 Entry 1: In an argon-filled glovebox, a vial (10 ml) was charged with (PSCOP)IrHCl (1) (0.5 mol%), NaBHEt 3 (1.0 mol%), n-hexane (1.0 ml), trans-3-octene (0.2 mmol), MD M (0.2 mmol). The reaction mixture was stirred at room temperature for 12 h. After that, the reaction was quenched by exposing the solution to air. Mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. Primary octylsilane 6a was not detected by GC, and two branched octylsilanes resulting from the hydrosilylation of trans-3-octene (6% yield) were detected. Entries 2-5: In an argon-filled glovebox, a vial (10 ml) was charged with Fe-precatalyst (2a, 2b, 2c or 2d, 5.0 mol%), n-hexane (1.0 ml), trans-3-octene (0.2 mmol), MD M (0.2 mmol), NaBHEt 3 (10.0 mol%). The NATURE CHEMISTRY S-2 2

3 reaction mixture stirred at room temperature for 12 h. After that, the reaction was quenched by exposing the solution to air. Mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. Entries 6-7: In an argon-filled glovebox, a vial (10 ml) was charged with (PSCOP)IrHCl (1) (0.5 mol%), Fe-precatalyst (2c or 2d, 5.0 mol%), n-hexane (1.0 ml), trans-3-octene (0.2 mmol), MD M (0.2 mmol), NaBHEt 3 (11.0 mol%). The reaction mixture was stirred at room temperature for 12 h. After that, the reaction was quenched by exposing the solution to air. Mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. The effect of diene on Fe-catalyzed olefin isomerisation-hydrosilylation In an argon-filled glovebox, a vial (10 ml) was charged with (PSCOP)IrHCl (1) (0.5 mol%), Fe-precatalyst 2c (5.0 mol%), p-xylene (1.0 ml), (E)-deca-1,3-diene (27 mol%), trans-3-octene (0.2 mmol), MD M (0.2 mmol), NaBHEt 3 (11.0 mol%). The reaction mixture was stirred for 12 h at room temperature. After that, the reaction was quenched by exposing the solution to air, and mesitylene (10 µl) was added as internal standard. An aliquot was removed from the vial and analyzed by GC and GC-MS, which showed the reaction did not form any detectable alkylsilanes. The results suggest that dienes can inhibit Fe-catalyzed olefin isomerization-hydrosilylation, presumably through chelation on the iron center. Table S1. Evaluation of metal catalysts for tandem olefin isomerisation-hydrosilylation + (Me 3 SiO) 2 MeSiH 4 5 mol% precat. NaBHEt 3 n-hexane rt, 12 h nc 6 H 13 6a SiMe(OSiMe 3 ) 2 N tbu 2 P Fe Cl Cl 2a N Entry Precat. NaBHEt 3 [mol%] Yield [%] a of 6a 1 2a b c d e 10 23(5) 1/2 [Ir(cod)Cl] 2 /dppp 0 8(2) 1/2 [Rh(cod)Cl] 2 /dppp 0 NR 8 FeBr 2 10 NR 9 FeBr 2 /dppp 10 NR N N Fe N Ar Br Br Ar 2b, Ar = 2,6-iPr-C 6 H 3 2c, Ar = 2,6-Et-C 6 H 3 2d, Ar = 2,6-Me-C 6 H 3 N N Co N Ar Cl Cl Ar 2e, Ar = 1,3,5-Me-C 6 H 2 a Determined by GC using mesitylene as an internal standard. Numbers in the parenthesis are yields of branched products. NATURE CHEMISTRY 3

4 Table S2. Evaluation of the relative rates for isomerisation-hydrosilylation of 1-, 2-, and 3-octenes a Determined by GC using mesitylene as an internal standard 3. General procedures for Table 2 Reactions in neat alkanes (entries 1-5 and entries 12-15): In an argon-filled glovebox, a thick-wall Kontes flask (10 ml) was charged with (PSCOP)IrHCl (1) (1.0 mol%), NaOtBu (1.2 mol%), alkane (2.0 ml) and TBE (0.50 mmol). The flask was sealed with a Teflon plug under an argon atmosphere, and the solution stirred in a 200 C oil bath for allotted time. After that, the flask was cooled to room temperature, and ( Et PDI)FeBr 2 (2c) (10.0 mol%), MD M or Et 2 SiH 2 (0.50 mmol), NaBHEt 3 (20.0 mol%) were added to the solution in an argon-filled glovebox. The flask was then sealed with a Teflon plug under an argon atmosphere, and the solution continued to stir for 12 h at room temperature. The reaction was then quenched by exposing the solution to air, and mesitylene (20 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. Elution of the resulting solution through a silica gel plug with n-hexane afforded the crude products, which typically include the desired product, the side-product resulting from hydrosilylation of unreacted t-butylethylene (TBE), and the unreacted alkane substrate. The crude products were further purified by removal of the side-product and unreacted substrate by evaporation under reduced pressure to afford the pure alkane silylation product. Reactions in p-xylene (entries 6-11, and 16): In an argon-filled glovebox, a thick-wall Kontes flask (10 ml) was charged with (PSCOP)IrHCl (1) (1.0 mol%), NaOtBu (1.2 mol%), p-xylene (2.0 ml), alkane [1.5 S-4 NATURE CHEMISTRY 4

5 mmol except for entry 8 (2.5 mmol)] and TBE (0.50 mmol). The flask was sealed with a Teflon plug under an argon atmosphere, and the solution stirred in a 200 C oil bath for allotted time. After that, the flask was cooled to room temperature, and ( Et PDI)FeBr 2 (2c) or ( Me PDI)FeBr 2 (2d) (10.0 mol%), MD M or Et 2 SiH 2 (0.50 mmol), NaBHEt 3 (20.0 mol%) were added to the solution in an argon-filled glovebox. The flask was then sealed with a Teflon plug under an argon atmosphere, and the solution continued to stir for 12 h at room temperature. The reaction was then quenched by exposing the solution to air, and mesitylene (20 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. The resulting solution was concentrated under vacuum, and the residue was purified by elution through a silica gel plug with n-hexane and removal of the side-product and unreacted substrate by evaporation under reduced pressure to afford the pure alkane silylation product. 3-(3,3-dimethylbutyl)-1,1,1,3,5,5,5-heptamethyltrisiloxane 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), 0.84 (s, 9 H), (m, 2 H), 0.09 (s, 18 H), (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 37.1, 31.0, 29.0, 12.0, 2.0, The spectroscopic data correspond to the reported data 6. 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane (6a) 1 H NMR (400 MHz, CDCl 3 ): δ 1.26 (m, 12 H), 0.88 (t, J = 6.8 Hz, 3 H), 0.45 (vt, J = 7.5 Hz, 2 H), 0.08 (s, 18 H), (s, 3 H). The spectroscopic data correspond to the reported data 7. 3-decyl-1,1,1,3,5,5,5-heptamethyltrisiloxane (6b) 1 H NMR (400 MHz, CDCl 3 ): δ 1.26 (m, 16 H), 0.88 (t, J = 6.7 Hz, 3 H), 0.44 (vt, J = 7.6 Hz, 2 H), 0.08 (s, 18 H), (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 33.5, 32.2, 29.9, 29.8, 29.6, 29.5, 23.3, 22.9, 17.8, 14.3, 2.0, HRMS (EI), m/z calcd. for C 16 H 39 O 2 Si 3 (M-CH + 3 ) , found: NATURE CHEMISTRY S-5 5

6 3-hexyl-1,1,1,3,5,5,5-heptamethyltrisiloxane (6c) 1 H NMR (400 MHz, CDCl 3 ): δ 1.28 (m, 8 H), 0.89 (t, J = 6.9 Hz, 3 H), 0.45 (t, J = 7.7 Hz, 2H), 0.08 (s, 18 H), (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 33.3, 32.0, 23.4, 22.9, 17.9, 14.4, 2.05, The spectroscopic data correspond to the reported data 8. 1,1,1,3,5,5,5-heptamethyl-3-(6-methylheptyl)trisiloxane (6d) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 6 H), (m, 2 H), 0.86 (d, J = 6.6 Hz, 6 H), 0.45 (vt, J = 7.7 Hz, 2 H), 0.08 (s, 18 H), (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 39.1, 33.7, 28.2, 27.3, 23.3, 22.8, 17.8, 2.0, HRMS (EI), m/z calcd. for C 15 H 38 O 2 Si 3 (M-CH + 3 ) , found: ,1,1,3,5,5,5-heptamethyl-3-(4-(trimethylsilyl)butyl)trisiloxane (6e) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4 H), (m, 4 H), 0.08 (s, 18 H), (s, 3 H), (s, 9 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 27.8, 27.3, 17.6, 16.7, 2.03, -0.09, HRMS (EI), m/z calcd. for C 13 H 35 O 2 Si 4 (M-CH + 3 ) , found: (4,4-dimethylpentyl)-1,1,1,3,5,5,5-heptamethyltrisiloxane (6f) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 2 H), 0.86 (s, 9 H), (m, 2 H), 0.09 (s, 18 H), 0.00 (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 48.5, 30.7, 29.6, 18.7, 18.3, 2.1, ,1,1,3,5,5,5-heptamethyl-3-(3-phenylpropyl)trisiloxane (6g) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 3 H), 2.62 (m, 2 H), (m, 2 H), (m, 2 H), 0.08 (s, 18 H), 0.00 (s, 3 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 142.9, 128.6, 128.4, 125.8, 39.6, 25.4, 17.6, 2.03, The spectroscopic data correspond to the reported data 9. NATURE CHEMISTRY S-6 6

7 3-(3-(4-methoxyphenyl)propyl)-1,1,1,3,5,5,5-heptamethyltrisiloxane (6h) 1 H NMR (400 MHz, CDCl 3 ): δ 7.08 (d, J = 8.6 Hz, 2 H), 6.83 (d, J = 8.6 Hz, 2 H), 3.79 (s, 3 H), (t, J = 7.5 Hz, 2 H), (m, 2 H), (m, 2 H), 0.07 (s, 18 H), (s, 3 H). 3-(3-(3-fluorophenyl)propyl)-1,1,1,3,5,5,5-heptamethyltrisiloxane (6i) 1 H NMR (400 MHz, CDCl 3 ): δ 7.23 (m, 1 H), 7.07 (s, 1 H), (m, 2 H), 2.61 (t, J = 7.6 Hz, 2 H), (m, 2 H), (m, 2H), 0.08 (s, 18H), 0.00 (s, 3 H). 19 F NMR (376 MHz, CDCl 3 ): δ diethyl(octyl)silane (7a) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 12 H), 0.97 (t, J = 7.9 Hz, 6 H), 0.88 (t, J = 6.8 Hz, 3 H), (m, 6 H). The spectroscopic data correspond to the reported data 10. Decyldiethylsilane (7b) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 16 H), 0.97 (t, J = 7.9 Hz, 6 H), 0.88 (t, J = 6.8 Hz, 3 H), (m, 6 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 33.6, 32.1, 29.8, 29.8, 29.5, 24.8, 22.9, 14.3, 10.8, 8.4, 3.0. HRMS (EI), m/z calcd. for C 14 H 32 Si (M + ) , found: diethyl(hexyl)silane (7c) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 8 H), 0.97 (t, J = 7.9 Hz, 6 H), 0.88 (t, J = 6.9 Hz, 3 H), (m, 6 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 33.2, 31.8, 24.7, 22.8, 14.3, 10.8, 8.4, 3.0. NATURE CHEMISTRY S-7 7

8 diethyl(6-methylheptyl)silane (7d) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 1 H), (m, 6 H), (m, 2 H), 0.97 (t, J = 7.9 Hz, 6 H), 0.86 (d, J = 6.6 Hz, 6 H), (m, 6 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 39.2, 33.9, 28.2, 27.3, 24.8, 22.8, 10.8, 8.4, 3.0. HRMS (EI), m/z calcd. for C 12 H 27 Si (M + ) , found: (3-(diethylsilyl)propyl)trimethylsilane (7e) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1 H), (m, 4 H), 0.97 (t, J = 7.9 Hz, 6 H), (m, 4 H), 0.48 (t, J = 9.2 Hz, 2 H), (s, 9 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 28.7, 27.9, 16.6, 10.5, 8.4, 3.0, HRMS (EI), m/z calcd. for C 10 H 25 Si 2 (M + ) , found: Procedures for Table 3 Entries 1-4: In an argon-filled glovebox, a thick-wall Kontes flask (10 ml) was charged with (PSCOP)IrHCl (1) (1.0 mol%), NaOtBu (1.2 mol%), alkane (1.0 ml) and TBE (0.25 mmol). The flask was sealed with a Teflon plug under an argon atmosphere, and the solution was stirred in a 200 C oil bath for allotted time. After that, the flask was cooled to room temperature, and (PNN)FeCl 2 (2a) (10.0 mol%), HBPin (0.25 mmol), NaBHEt 3 (20.0 mol%) were then added to the solution in an argon-filled glovebox. The flask was then sealed with a Teflon plug under an argon atmosphere, and the solution continued to stir for 12 h at room temperature. The reaction was then quenched by exposing the solution to air, and mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. Entries 5 and 7: In an argon-filled glovebox, a thick-wall Kontes flask (10 ml) was charged with (PSCOP)IrHCl (1) (1.0 mol%), NaOtBu (1.2 mol%), p-xylene (1.0 ml), alkane (0.75 mmol) and TBE (0.25 mmol). The flask was sealed with a Teflon plug under an argon atmosphere, and the solution was stirred in a 200 C oil bath for allotted time. After that, the flask was cooled to room temperature, and (PNN)FeCl 2 (2a) (10.0 mol%), HBPin (0.25 mmol), NaBHEt 3 (20.0 mol%) were added to the solution in an argon-filled glovebox. The flask was then sealed with a Teflon plug under an argon atmosphere, and the solution continued to stir for 12 h at room temperature. The reaction was then quenched by exposing the solution to air, and mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. Entry 6: In an argon-filled glovebox, a thick-wall Kontes flask (10 ml) was charged with (PSCOP)IrHCl NATURE CHEMISTRY S-8 8

9 (1) (1.0 mol%), NaOtBu (1.2 mol%), p-xylene (1.0 ml), 2,4-dimethylhexane (1.25 mmol) and TBE (0.25 mmol). The flask was sealed with a Teflon plug under an argon atmosphere, and the solution was stirred in a 200 C oil bath for allotted time. After that, the flask was cooled to room temperature, and (PNN)FeCl 2 (2a) (10.0 mol%), HBPin (0.25 mmol), NaBHEt 3 (20.0 mol%) were added to the solution in an argon-filled glovebox. The flask was then sealed with a Teflon plug under an argon atmosphere, and the solution continued to stir for 12 h at room temperature. The reaction was then quenched by exposing the solution to air, and mesitylene (10 µl) was then added as internal standard. An aliquot was removed from the vial and analyzed by GC. 5. General procedures for preparation of the standard alkylboronates (for measurements of their GC response factors relative to mesitylene) In an argon-filled glovebox, a vial (10 ml) was charged with (PNN)FeCl 2 (2a) (0.5 mol%), n-hexane or toluene (1.0 ml), HBPin (0.5 mmol), α-olefin (0.5 mmol), NaBHEt 3 (1.0 mol%). The reaction mixture was stirred for 2 h at room temperature. Then the reaction was quenched by exposing the solution to air. The resulting solution was concentrated under vacuum and the residue was purified by elution through a silica gel plug with n-hexane and ethyl acetate. 2-(3,3-dimethylbutyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane 1 H NMR (400 MHz, CDCl 3 ): δ 1.28 (t, J = 8.6 Hz, 2 H), 1.24 (s, 12 H), 0.84 (s, 9 H), 0.71 (t, J = 8.6 Hz, 2 H). The spectroscopic data correspond to the reported data 3. 4,4,5,5-tetramethyl-2-octyl-1,3,2-dioxaborolane (8a) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 10 H), 1.24 (m, 12 H), 0.87 (t, J = 6.9 Hz, 3 H), 0.76 (t, J = 7.8 Hz, 2 H). The spectroscopic data correspond to the reported data 11. NATURE CHEMISTRY S-9 9

10 2-decyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (8b) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 26 H), 0.87 (t, J = 6.8 Hz, 3 H), 0.76 (t, J = 7.7 Hz, 2 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 82.9, 32.6, 32.1, 29.8, 29.7, 29.6, 29.5, 24.9, 24.1, 22.8, The spectroscopic data correspond to the reported data hexyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (8c) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 6 H), 1.24 (s, 12 H), 0.87 (t, J = 6.9 Hz, 3 H), 0.76 (t, J = 7.7 Hz, 2 H). The spectroscopic data correspond to the reported data 13. trimethyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)butyl)silane (8e) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 2 H), 1.24 (s, 12 H), 0.77 (t, J = 7.7 Hz, 2 H), (m, 2 H), (s, 9 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 82.9, 28.1, 26.8, 24.9, 16.6, HRMS (EI), m/z calcd. for C 13 H 29 O 2 Si 10 B (M + ) , found: ,4,5,5-tetramethyl-2-(3-phenylpropyl)-1,3,2-dioxaborolane (8g) 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2 H), (m, 3 H), 2.60 (t, J = 7.6 Hz, 2 H), 1.75 (m, 2 H), 1.26 (s, 12 H), 0.85 (t, J = 8.0 Hz, 2 H). 13 C{ 1 H} NMR (101 MHz, CDCl 3 ): δ 142.7, 128.6, 128.2, 125.6, 82.9, 38.7, 26.2, The spectroscopic data correspond to the reported data 3. NATURE CHEMISTRY S-10 10

11 6. References 1. Shimada, S.; Batsanov, A. S.; Howard, J. A. K.; Marder, T. B. Angew. Chem., Int. Ed. 2001, 40, Yao, W.; Zhang, Y.; Jia, X.; Huang, Z. Angew. Chem., Int. Ed. 2014, 53, Zhang, L.; Peng, D.; Leng, X.; Huang, Z. Angew. Chem., Int. Ed. 2013, 125, Small, B. L.; Brookhart, M.; Bennett, A. M. A. J. Am. Chem. Soc. 1998, 120, Schmidt, R.; Welch, M. B.; Palackal, S. J.; Alt, H. G. J. Mol. Catal. A: Chem. 2002, 179, Firgo, H. A.; Weber, W. P. Organometallics 1982, 1, Peng, D.; Zhang, Y.; Du, X.; Zhang, L.; Leng, X.; Walter, M. D.; Huang, Z. J. Am. Chem. Soc. 2013, 135, Greenhalgh, M. D.; Frank, D. J.; Thomas, S. P. Adv. Synth. Catal. 2014, 356, Bandari, R.; Buchmeiser, M. R. Catal. Sci. Technol. 2012, 2, Steiman, T. J.; Uyeda, C. J. Am. Chem. Soc. 2015, 137, Lata, C. J.; Crudden, C. M. J. Am. Chem. Soc. 2010, 132, Atack, T. C.; Lecker, R. M.; Cook, S. P. J. Am. Chem. Soc. 2014, 136, Yi, J.; Liu, J. H.; Liang, J.; Dai, J. J.; Yang, C. T.; Fu, Y.; Liu, L. Adv. Synth. Catal. 2012, 354, NATURE CHEMISTRY S-11 11

12 7. NMR spectra for isolated compounds 1 H NMR (400 MHz, CDCl 3 ) for 6a NATURE CHEMISTRY S-12 12

13 1 H NMR (400 MHz, CDCl 3 ) for 6b NATURE CHEMISTRY S-13 13

14 13 C NMR (101 MHz, CDCl 3 ) for 6b NATURE CHEMISTRY S-14 14

15 1 H NMR (400 MHz, CDCl 3 ) for 6c NATURE CHEMISTRY S-15 15

16 1 H NMR (400 MHz, CDCl 3 ) for 6d NATURE CHEMISTRY S-16 16

17 13 C NMR (101 MHz, CDCl 3 ) for 6d NATURE CHEMISTRY S-17 17

18 1 H NMR (400 MHz, CDCl 3 ) for 6e NATURE CHEMISTRY S-18 18

19 13 C NMR (101 MHz, CDCl 3 ) for 6e NATURE CHEMISTRY S-19 19

20 1 H NMR (400 MHz, CDCl 3 ) for 6f NATURE CHEMISTRY S-20 20

21 13 C NMR (101 MHz, CDCl 3 ) for 6f NATURE CHEMISTRY S-21 21

22 1 H NMR (400 MHz, CDCl 3 ) for 6g NATURE CHEMISTRY S-22 22

23 13 C NMR (101 MHz, CDCl 3 ) for 6g NATURE CHEMISTRY S-23 23

24 1 H NMR (400 MHz, CDCl 3 ) for 7a S-24 NATURE CHEMISTRY 24

25 1 H NMR (400 MHz, CDCl 3 ) for 7b NATURE CHEMISTRY S-25 25

26 13 C NMR (101 MHz, CDCl 3 ) for 7b NATURE CHEMISTRY S-26 26

27 1 H NMR (400 MHz, CDCl 3 ) for 7c NATURE CHEMISTRY S-27 27

28 1 H NMR (400 MHz, CDCl 3 ) for 7d NATURE CHEMISTRY S-28 28

29 13 C NMR (101 MHz, CDCl 3 ) for 7d S-29 NATURE CHEMISTRY 29

30 1 H NMR (400 MHz, CDCl 3 ) for 7e NATURE CHEMISTRY S-30 30

31 13 C NMR (101 MHz, CDCl 3 ) for 7e NATURE CHEMISTRY S-31 31