Supporting Information

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1 Supporting Information Visible Light-Promoted Selective Oxidation of Alcohols Using a Covalent Triazine Framework Wei Huang, Beatriz Chiyin Ma, Hao Lu, Run Li, Lei Wang, Katharina Landfester and Kai A. I. Zhang* Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz, Germany kai.zhang@mpip-mainz.mpg.de Materials: 2.5-dibromothiophene, copper cyanide, tetraethylorthosilicate (TEOS) and trifluromethanesulfonic acid (TfOH) and benzotrifluoride were purchased from Sigma-Aldich. All chemicals and solvents were used without further purification. Synthesis of 2,5-dicyanothiophene (DCT): 2,5-dicyanothiophene was synthesized according to the literature. 1 Typically, a mixture of 2,5-dibromothiophene (2.0 g, 8.3 mmol, 1 eq), CuCN (2.2 g, 24.6 mmol, 3 eq) and N,N-dimethylmethanamide (10 ml) in a 50 ml flash was refluxed at 140 o C under nitrogen atmosphere for 12 h. After cool to 60 o C, FeCl 3 6H 2 O (13 g) in 2M HCl (30 ml) was added into the reaction solution. The mixture was then vigorously stirred at 60 o C for 4 h. When cooled down to room temperature, the mixture was extracted with dimethane chloride (100 ml 3). The combined organic phase was washed with diluted HCl and Milli Q water, dried with anhydrous Na 2 SO 4. The filtrate was concentrated under vacuum and purified through a silica column eluting with hexane/ dimethane chloride (1:1). The product was obtained as colorless needles (yield 54 %). 1 H NMR (300 MHz, CDCl 3 ) δ (7.57, 2H); 13 C NMR (300 MHz, CDCl 3 ) δ , , Synthesis of mesoporous silica SBA-15: Silica SBA-15 was synthesized according to the literature. 2 Simply, Pluronic P123 (4.0 g) was first added into a mixture of Mill-Q water (30 ml) and 2M HCl aqueous solution (120 ml), which was stirred at 35 C overnight. Then tetraethylorothosilicate (TEOS) (9.1 ml) was slowly added into the solution under vigorous stirring. The mixture was kept at 35 C for 24 h in static conditions, followed by heated to 100 S1

2 C for another 24 h. the resulting white precipitate was collected by centrifugation, washed with water and dried. Finally, it was calcined at 550 C in air for 4 h to remove the surfactant. Fabrication of CTF-Th@SBA-15: The CTF-Th@SBA-15 was prepared by TfOH vaporassisted solid phase reaction routine according to our previous report. 3 In a typical procedure, 200 mg vacuum-dried silica SBA-15 was dispersed in a solution of 2,5-dicyanothiophene (DCT) (100 mg, 0.75 mmol) and tetrahydrofuran (2 ml), followed by stirred for 2 h under vacuum. The solvent was then slowly evaporated by a rotary evaporator to give the monomer casted precursor DCT/SBA-15. The precursor was further annealed at 80 C for 2 h before transferred into a conical flask, in which there was another vial with 0.3 ml TfOH. The conical flask was degassed with nitrogen, sealed and heated up to 100 C in an oven for 24 hours. After cooled down to room temperature, the product was immersed in water and washed with distilled aqueous ammonia and Milli Q water to remove the residual TfOH. Further purification was conducted by continuous washing the sample with methanol and acetone, followed by drying at 80 C under vacuum overnight. To obtain the pure CTF-Th, the silica was etched with 4 M ammonium bifluoride (NH 4 HF 2 ) solution for 30 h followed by careful washing with water and ethanol. Characterization: UV-Vis absorption was recorded at room temperature on a Perkin Elmer Lambda 100 spectrophotometer. Liquid 1 H NMR and 13 C NMR measurements were conducted on Bruker Bruker AVANCE 300 system. FT-IR sepctra were carried out on a Varian 1000 FT-IR spectrometer. Solid State 13 C CP MAS NMR measurements were carried out using Bruker Avance II solid state NMR spectrometer operating at 300 MHz Larmor frequency equipped with a standard 4mm magic angle spinning (MAS) double resonance probe head. Scanning electron microscope (SEM) images were acquired on a LEO Gemini 1530 (Carl Zeiss AG), using an in lens SE detector. High resolution Transmission electron microscope (HR-TEM) images were performed on a FEI Tecnai F20 with an EDX detector. Electron paramagnetic resonance (EPR) was measured on a Magnettech Miniscope MS200 spectrometer at room temperature. The thermal gravity analysis (TGA) measurement was conducted under oxygen with temperature increasing from 25 o C to 800 o C at a rate of 10 o C/min. BET surface areas and pore size distributions were measured by nitrogen adsorption and desorption at 77 K using Autosorb 1 S2

3 (Quantachrome Instruments). Samples were degassed at 150 o C for 24 h under high vacuum before analysis. The BET surface area calculation was based on data points obtained from 0<P/P 0 <0.25 and the nonlinear density functional theory (NLDFT) equilibrium model was used for the BET model fitting. Pore size distributions and pore volumes were derived from the adsorption branches of the isotherms using Quenched Solid Density Functional Theory (QSDFT, N 2, assuming carbon adsorbent with slit pores). X-ray diffraction (XRD) was conducted on a Philips PW 1820 diffractometer with monochromatic Cu Kα radiation. X-ray photoelectron spectroscopy (XPS) measurements were performed on a Kratos AXIS Ultra DLD instrument using a monochromatic Al Ka x-ray source. Cyclic voltammetry (CV) measurement was performed using an Autolab PGSTAT204 potentiostat/galvanostat (Metrohm). Glassy carbon electrode drop-casted with the polymers as the working electrode, Pt wire as the counter electrode, Hg/HgCl (in saturated KCl solution) electrode as the reference electrode, Bu 4 NPF 6 (0.1 M in acetonitrile) was used as electrolyte. The reduction potential was recorded with a scan rate of 100 mv/s. General procedure for photocatalytic oxidation reactions: Typically, 0.1 mmol substrate, 10 mg CTF-Th@SBA-15 was suspended in 1.5 ml benzotrifluoride in a 20 ml glass vessel. Oxygen was bubbled into the mixture for 5 min using an oxygen balloon. The reaction vessel was then irradiated with a blue LED lamp (λ=460 nm, 0.16 W/cm 2 ) for 4 hours for the oxidation of alcohols. The reaction temperature was kept at room temperature by a water bath. After the reaction was completed, the catalyst was separated out by centrifugation. The conversion and selectivity were determined by GC-MS. S3

4 Figure S1. Photography of in (a) solid state and (b) a suspension in benzotrifluoride (0.1 mg/ml) as well as the corresponding fluorescent pictures under UV light (365 nm); c) emission spectrum of CTF-Th@SBA-15 irradiated at 365 nm. S4

5 Figure S2. a) BET surface area and b) pore size distribution of pure CTF-Th obtained after removing SBA-15 support. Figure S3. a) SEM and b) TEM images of pure CTF-Th obtained after the removal of SBA-15 support. The disappearance of ordered 1D channels, as indicated by TEM, indicates the structural collapse of the CTF-Th after removing the silica support, which in turn resulting in the significant decrease of the BET surface area. S5

6 Table S1. Additional surface area and porosity data. Samples S BET (m 2 /g) Total pore volume (cm 3 /g) Main pore size distribution (nm) Average pore size (nm) SBA CTF-Th@SBA CTF-Th after removal of SBA S6

7 Figure S4. TGA curve of obtained under oxygen atmosphere at a heating rate of 10 C/min. The CTF-Th exhibited excellent thermal stability up to 268 o C and start to loss for the bulk material at 517 o C under oxygen. The weigh content of pure CTF-Th in CTF-Th@SBA- 15 was estimated to be 32.6%. The weight of the residual SiO 2 at 650 C increased owing to the formation of SiO x (x>2). 4 S7

8 Figure S5. The solid state 13 C cross-polarization magic-angle-spinning (CP-MAS) NMR of CTF-Th@SBA-15 and CTF-Th after etching the silica. S8

9 Table S2. Elemental analysis data of CTF-Th before and after treatment by NH 4 HF 4 (4M) for 48 hours. Sample C N S H Calculated (%) CTF-Th-Before CTF-Th-After S9

10 Figure S6. FT-IR spectra of SBA-15, and CTF-Th after removing the silica. S10

11 Figure S7. S 2p XPS spectrum of the CTF-Th. Figure S8. XRD pattern of CTF-Th obtained after the removal of silica support. S11

12 Figure S9. Band gap of obtained from the UV/Vis DR spectrum according to the Kubelka Munk theory. Figure S10. Reduction potential of measured by cyclic voltammetry. S12

13 Figure S11. EPR spectra of obtained in the dark and under visible light irradiation. S13

14 Figure S12. Monitored conversion of benzyl alcohol to benzaldehyde at different reaction times. S14

15 Figure S13. EPR spectra of DMPO-O 2. Conditions: 2 mg Photocatalyst (CTF-Th@SBA-15) was dispersed in 0.1 M DMPO (3 ml in CH 3 CN), the solution was continuously irradiated for 5 min with a blue lamp (λ=460 nm) before measurement. Figure S14. EPR spectra of TEMP- 1 O 2. Conditions: 2 mg Photocatalyst (CTF-Th@SBA-15) was dispersed in 0.1 M TEMP (3 ml in CH 3 CN), the solution was continuously irradiated for 5 min with a blue lamp (λ=460 nm) before measurement. S15

16 Figure S15. UV/Vis absorption spectra of the tri-iodide formed by H 2 O 2 oxidation. We confirmed the formation of H 2 O 2 by UV/Vis monitor of tri-iodide (I 3 - ) in aqueous solution. When over amount of I - was added the reaction solution, the I - can be oxidized to I 2 by H 2 O 2, subsequently, the I 2 further react with I - to form I 3 -, which shows two characteristic peaks at ca. 300 and 350 nm in UV/Vis spectra. 5 Figure S16. Kinetic isotope effect (KIE) study. The total conversion (C t %) was determined by GCMS. The conversion of benzyl alcohol (C h %) was estimated by 1 H NMR. Correspondingly, the conversion of deuterated benzyl alcohol (C d %) can be obtained according to the formula: C d %= 2*C t %- C h %. S16

17 Table S3. Comparison of different state-of-art photocatalytic systems for selective oxidation of benzyl alcohol. Photocatalyst 15 Alizarin Red/DEMPO /TiO 2 Monolayer HNb 3 O 8 t (h) Cat. Concentration (mg/ml) Atmosphere Conv. (%) Sel. (%) TOF (mol/g/h) ( 10 3 ) c) O 2 >99 > O 2 (0. 1 MPa) O 2 20 > Ref. this work 6 7 Pd@CeO O 2 28 > CdS@UiO O 2 (0.1 MPa) 30 > Pt 0.8 Cu 0.2 /TiO O mpg-carbon nitride a) 3 5 O 2 (8 bar) 57 > Thiophenecarbon nitride b) O 2 53 > Sulfuric acid modified carbon 4 5 O nirtide c) rgo-cns 8 12 O Pt@Porphyrinic MOF O 2 > a,c) reaction temperature: 100 C; b) reaction temperature: 60 C; c) based on the weight content of CTF-Th in CTF-Th@SAB S17

18 Figure S17. Repeat experiments of the oxidation of benzyl alcohol to benzaldehyde. S18

19 Figure S18. UV-Vis DR spectra of before and after 5 reaction cycles. S19

20 Figure S19. FT-IR spectra of the photocatalsts before and after five reaction cycles. S20

21 Figure S20. The UV-Vis spectra of the model compound 2,4,6-tri(thiophen-2-yl)-1,3,5-triazine in solution and solid state. Note: We also tested the photocatalytic activity of the model compound: 2,4,6-tri(thiophen-2- yl)-1,3,5-triazine as shown above. The model compound was synthesized according to the literature. 16 Owing to the lack of absorbance in the visible light region, the conversion with the model compound as photocatalyst under the standard condition is lower than 1 % after 24 hours. S21

22 Additional Data Figure S21. (a) Structures of CTF-Th and CTF-1, (b) UV-Vis DR spectra and (c) PL spectra of SBA-15, and Note: We tested the photocatalytic activity of CTF-1 as the first example of covalent triazine framework. The catalytic efficiency was indeed very poor, no obvious conversion could be determined. The reason should be its limited absorption in the visible range. S22

23 SEM images Figure S22. Typical HR-SEM and TEM images of pure SBA-15. S23

24 Figure S23. HR-TEM images of S24

25 Figure S24. a) 1 H NMR and b) 13 C NMR spectra of 2,5-dicyanothiophene (DCT) in CDCl 3. S25

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