Sharareh Bagherzadeh and Neal P. Mankad* Department of Chemistry, University of Illinois at Chicago, Chicago, IL *

Transcription

1 Catalyst Control of Selectivity in CO 2 Reduction Using a Tunable Heterobimetallic Effect Sharareh Bagherzadeh and Neal P. Mankad* Department of Chemistry, University of Illinois at Chicago, Chicago, IL * npm@uic.edu Supporting Information Contents: General Considerations Catalytic Reactions (Procedures & Spectra) CO Trapping Experiment (Procedures & Spectra) Peak Assignments for pinboh and (pinb) 2 O GC-MS detection of CO Catalysis with (IPr)CuOtBu + FpBpin (Procedures & Spectra) Decarbonylation Activity of FpBpin ((Procedures & Spectra) S2 S3 S15 S18 S20 S21 S23 S1

2 General considerations. All reactions and manipulations were conducted under purified N 2 using standard Schlenk line techniques or in a glovebox. Deuterated benzene (C 6 D 6 ) was degased by repeated freeze-pump-thaw cycles and stored over activated 3-Å molecular sieves prior to use. 1 H and 13 C NMR spectra were recorded using Bruker Avance 400-MHz NMR spectrometer. NMR spectra were recorded at room temperature, and chemical shifts were referenced to residual solvent peak. 11 B NMR chemical shifts were referenced to external pinacolborane (29.0 and 27.6 ppm). The 1 H NMR and 11 B NMR data of PinBOCOH, 1a PinBOH, 1b and (Pin) 2 B 2 O, 1c matched literature values. Literature methods were used to synthesize NaWp, 2 IMes HCl, IPr HCl, 3 (IMes)CuCl, (IPr)CuCl, 4 (IMes)CuFp, (IPr)CuFp, 5 (IPr)CuMp, (IMes)CuMp, (IMes)CuWp, (IPr)CuWp, 6 Cp*RuCl(PCy3), 7 and FpBpin. 8 1 (a) Bontemps, S.; Vendier, L.; Sabo-Etienne, S. Angew. Chem. Int. Ed. 2012, 51, (b) Sueki, S.; Kuninobu, Y. Org. Lett. 2013, 15 (7), (c) Hawkeswood, S.; Stephan, D. W. Dalton Trans. 2005, Behrens, U.; Edelmann, F. J. Organomet. Chem. 1984, 263, (a) Jafarpour, L.; Stevens, E. D.; Nolan, S. P. J. Organomet. Chem. 2000, 606, (b) Arduengo, A. J., III; Krafczyk, R.; Schmutzler, R.; Craig, H. A.; Goerlich, J. R.; Marshall, W. J.; Unverzagt, M. Tetrahedron 1999, 55, (c) Hintermann, L. Beilstein J. Org. Chem. 2007, 3, (a) Santoro, O.; Collado, A.; Slawin, A. M. Z.; Nolan, S. P.; Cazin, C. S. J. J. Chem Soc., Chem. Comm. 2013, 49, (b) Kaur, H.; Zinn, F. K.; Stevens, E. D.; Nolan, S. P. Organometallics 2004, 23, Jayarathne, U.; Mazzacano, T. J; Bagherzadeh, S.; Mankad, N.P. Organometallics 2013, 32 (14), Banerjee, S.; Karunananda, M. K.; Bagherzadeh, S.; Jayarathne, U.; Parmelee, S. R.; Waldhart, G. W.; Mankad, N. P. Inorg. Chem. 2014, 53(20), Campion, B.; Heyn, R.; Tilley, D. J. Chem. Soc., Chem. Commun. 1988, Mazzacano, T. J., & Mankad, N. P. J. Am. Chem. Soc. 2013, 135, S2

3 Catalytic reduction of CO 2 by (IMes)Cu-Mp: In a nitrogen filled glovebox, (IMes)Cu-Mp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (42.6 µl, 0.29 mmol) and mesitylene (40.3 µl, 0.29 mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. 1 S3

4 5 Figure S1. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IMes)Cu-Mp S4

5 Catalytic reduction of CO 2 by (IMes)Cu-Wp: In a nitrogen filled glovebox, (IMes)Cu-Wp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (37.2 µl, 0.26 mmol) and mesitylene (36.2 µl, 0.26 mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. 1,2 S5

6 5 6 Figure S2. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IMes)Cu-Wp S6

7 Catalytic reduction of CO 2 by (IMes)Cu-Fp: In a nitrogen filled glovebox, (IMes)Cu-Fp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (47.9 µl, 0.33 mmol) and mesitylene (45.9 µl, 0.33mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. 1,2 S7

8 5 6 Figure S3. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IMes)Cu-Fp S8

9 Catalytic reduction of CO 2 by (IPr)Cu-Mp: In a nitrogen filled glovebox, (IPr)Cu-Mp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (37.7 µl, 0.26 mmol) and mesitylene (36.2 µl, 0.26 mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. 1,2 3 4 S9

10 5 HBpin 6 Figure S4. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IPr)Cu-Mp. S10

11 Catalytic reduction of CO 2 by (IPr)Cu-Wp: In a nitrogen filled glovebox, (IPr)Cu-Wp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (33.4 µl, 0.23 mmol) and mesitylene (32µL, 0.23 mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. S11

12 1,2 3 4 S12

13 5 6 HBpin Figure S5. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IPr)Cu-Wp. S13

14 Catalytic reduction of CO 2 by (IPr)Cu-Fp: In a nitrogen filled glovebox, (IPr)Cu-Fp (18 mg, mmol) was dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (41.5 µl, mmol) and mesitylene (39.8 µl, mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions S14

15 5 HBpin Figure S6. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IPr)Cu-Fp. S15

16 CO trapping experiment: In a nitrogen filled glovebox, (IMes)Cu-Fp (5 mg, mmol) was dissolved in C 6 D 6 (3 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (13 µl, 0.09mmol) was added. This solution was transferred to 50ml Schlenk flask with two arms. The Schlenk flask was taken out of the glovebox and connected to the Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reaction was exposed to CO 2 for 3 h and stirred for 36 h at room temperature. After 36 h another two-arm Schlenk flask was charged with Cp*RuCl(PCy 3 ) (50mg, 0.09mmol) and taken out of the glove box. The two flasks were connected together by adaptor (see Figure S7). The Cp*RuCl(PCy 3 ) containing flask was put under vacuum for 5 minutes and by opening the first flask, the CO gas and 2/3 of solution of this flask were transferred to the Cp*RuCl(PCy) 3 flask. The mixture of Ru complex, CO and solution were stirred for 3 h. It was then reintroduced into the glovebox and analyzed by 31 P NMR. The 31 P NMR chemical shift had moved downfield by 11ppm, consistent with what was observed by Cummins and coworkers. 9 (8) Jared, S.; Cummins, C. J. Am. Chem. Soc. 2010, 132(7) S16

17 Figure S7. Experimental apparatus for CO trapping experiment. The flask on the left contains CO evolving reaction catalyzed by (IMes)Cu-Fp. The flask on the right contains the CO trapping Ru reagent. S17

18 Figure S8. 31 P NMR spectra of the resulting mixture of Cp*RuCl(PCy 3 ) (40.6 ppm) and Cp*RuCl(PCy 3 )(CO) (51.6 ppm) as a result of trapping CO from the catalytic reduction of CO 2 with (IMes)Cu-Fp. S18

19 H 2 Figure S9. 1 H NMR spectra resulting from catalytic carbon dioxide reduction with (IPr)Cu-Mp, after adding extra pinacolborane (top) and before adding extra pinacolborane. S19

20 Figure S B NMR spectra resulting from catalytic carbon dioxide reduction with (IPr)Cu- Mp, after adding extra pinacolborane (top) and before adding extra pinacolborane. S20

21 Figure S11. GC-MS analysis of CO 2 reduction without catalyst (top) and in the presence of catalyst (bottom) S21

22 Catalytic reduction of CO 2 by (IPr)CuOtBu and FpBpin: In a nitrogen filled glovebox, (IPr)CuOtBu (18 mg, mmol) and FpBpin (10.4 mg, mmol) were dissolved in C 6 D 6 (6 ml) and pipette-filtered through Celite into another scintillation vial. Pinacolborane (49.7 µl, 0.34 mmol) and mesitylene (47.7 µl, 0.34 mmol) were added. This solution was transferred to three Schlenk flasks (2 ml of the solution in each Schlenk flask). The Schlenk flasks were taken out of the glove box and connected to a Schlenk line. The solutions were degassed by three freeze-pump-thaw cycles and backfilled with CO 2 (1 atm). The reactions were exposed to CO 2 for 36 h at room temperature. The conversion yields and error bars shown in Table 1 were calculated by 1 H NMR integration relative to the mesitylene internal standard, from an average of three independent reactions. 1,2 S22

23 6 5 Figure S12. 1 H NMR (top) and 11 B NMR (bottom) spectra resulting from catalytic carbon dioxide reduction with (IPr)CuOtBu and FpBpin. S23

24 In situ generation of 1, and its decarbonylation by FpBpin: To a typical product mixture containing a ~1:1 mixture of (2+3):1 generated by the typical catalytic procedure (see above), FpBpin (3.5 mg, mmol) was added under N 2 atmosphere. The reaction was analyzed by NMR spectroscopy at 8 h and 36 h. After 36 h, the solution was taken out of the glove box and connected to the Schlenk line and was exposed to the CO 2 for 24 h, then re-analyzed by NMR spectroscopy. d FpH c b FpBpin a Figure S13. (a) 1 H NMR spectrum of the initial mixture before adding FpBpin, (b) 1 H NMR spectrum of the reaction 8 h after adding FpBpin under N 2, (c) 1 H NMR spectra of the reaction 36 h after adding FpBpin under N 2, (d) 1 H NMR spectra of the reaction 24 h after exposing to CO 2. S24

25 pinbobpin PinBOCOH Figure S14. Same four 1 H NMR spectra from Figure S13, but zoomed in on Bpin region to show consumption of 1 and production of upon exposure to CO 2. S25

26 Fp- H Figure S15. Expanded view of spectrum in Figure S13d, showing the FpH hydride resonance. S26

27 Figure S16. (a) 11 B NMR spectrum of the initial mixture before adding FpBpin, (b) 11 B NMR spectrum of the reaction 8 h after adding FpBpin under N 2, (c) 11 B NMR spectra of the reaction 36 h after adding FpBpin under N 2, (d) 11 B NMR spectra of the reaction 24 h after exposing to CO 2. S27