Ferrocene-based poly ( aroxycarbonyltriazole ) s : synthesis by metal-free click polymerization and precursors to magnetic ceramics

a MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China. E-mail: qinaj@zju.edu.cn, tangbenz@ust.hk b Department of Chemistry, Institute for Advanced Study, and Institute of Molecular Functional Materials, The Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, China; c Guangdong Innovative Research Team, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China


S3
The 1 H and 13 C NMR spectra were recorded on a Bruker ADVANCE2B 300 or 400 NMR spectrometer in CDCl 3 or DMSO-d 6 using tetramethylsilane (TMS; δ = 0) as internal reference.The IR spectra were measured on a Bruker Vector 22 spectrometer as thin films on KBr disks.The MALDI-TOF mass spectra were conducted on a GCT premier CAB048 mass spectrometer.Thermo-gravimetric analysis (TGA) Philips PW 2830 powder diffractometer using monochromatized X-ray beam from a nickel-filtered Cu Kα radiation (λ = 1.5406Å).Magnetization curves were recorded on a Lake Shore 7037/9509-P vibrating sample magnetometer at room temperature.

Monomer Preparation
Ferrocenedicarboxaldehyde (4).Into a 500 mL two-necked round-bottom flask was placed 9.40 g (50 mmol) of ferrocene (3).The flask was evacuated under vacuum and flushed with dry nitrogen three times for 1 h.After dry hexane (150 mL) and N,N,N′,N′-tetramethylethylenediamine (TMEDA) (16.4 mL, 110 mmol) were injected, the mixture was stirred for 5 min at ambient temperature and subsequently 55 mL of n-butyllithium (2.0 M in hexane, 110 mmol) was added dropwise.After stirring at room temperature overnight, the solution was cooled to -78 o C and dry THF (75 mL) and DMF (8.56 mL, 110 mmol) were injected.The reaction mixture was then allowed to stir at room temperature for 1.5 h.Afterward, 30 mL of saturated brine was added to quench the reaction and the solution was extracted with DCM.The organic phase was separated and dried over MgSO 4 overnight.After filtration and solvent evaporation, the crude product was purified by a silica gel column using petroleum

Polymer Synthesis
Unless otherwise stated, all the polymerizations of dipropiolates 1 and ferrocene-containing diazide 2 were carried out under nitrogen using a standard Schlenk technique in a vacuum line system.Typical experimental procedures for the click polymerization of 1a with 2 are described below.
Into a 15 mL Schlenk tube with a stopcock in the side arm was placed 132.9 mg (0.4 mmol) of 1a and 118.4 mg (0.4 mmol) of 2. The tube was evacuated and refilled with dry nitrogen three times through the side arm.2.4 mL of DMF was injected into the tube to dissolve the monomers.After stirring at 80 o C for 24 h, the reaction mixture was diluted with 20 mL of chloroform and added dropwise into 500 mL of hexane through a cotton filter under stirring.The precipitates were allowed to stand overnight and then collected by filtration.The polymer was washed with hexane and dried to a constant weight at ambient atmosphere.8.28, 5.66, 5.42, 5.03, 4.41, 4.30, 4.21, 1.84. 13C NMR (100 MHz, DMSO-d 6 ), δ (TMS, ppm): 160.0, 139.3, 128.9, 82.9, 70.7, 69.9, 49.4, 27.3.

Pyrolytic Ceramization
Ceramics C3a, C3b and C3a were fabricated from the precursors P3a, P3b and P3c by pyrolysis in a tube furnace with a heating capacity up to 1700 °C.In a typical ceramization experiment, 200 mg of P3a was placed in a porcelain crucible, which was heated to 1000 °C at a heating rate of 10 °C/min under a steam of nitrogen.The sample was sintered at 1000 °C for 1 h, and black ceramic C3a was obtained in 35.4% yield (70.7 mg) after cooling to room temperature.

Fig. S4
Fig.S4IR spectra of monomers 1c (A) and 2 (B) and their polymer P3c (C).S9 photoelectron spectroscopy (XPS) experiments were performed on a PHI 5600 spectrometer (Physical Electronics) and the core level spectra were measured using a monochromatic Al Kα X-ray source (hv = 1386.6eV).The analyzer was operated at 23.5 eV pass energy and the analyzed area was 800 m in diameter.Structures of the ceramics were investigated on a high-resolution transmission electron microscopy (HRTEM) JEOL 2010F TEM.The X-ray diffraction diagrams were obtained on a Scheme S1 Synthetic routes to ferrocene-containing diazide monomer 2.

Table S1
Electrochemical data of P3 measured by CV.S17 Co., Ltd.(Shanghai, China).All other chemicals were purchased from Acros or Alfa, and used as received without further purification.Electronic Supplementary Material (ESI) for Polymer Chemistry This journal is © The Royal Society of Chemistry 2013 added portionwise until the solution reacted neutral.The reaction mixture was extracted and the organic phases were dried over MgSO 4 overnight.After filtration and solvent evaporation, the crude product was purified by a silica gel ether/ethyl acetate (2:1 by volume) as eluent.The dark red viscous oil of 4 was obtained in 52.0%yield (5.04 g). 1 H NMR (400 MHz, CDCl 3 ),  (TMS, ppm): 9.94 (s, 2H), 4.88 (t, 4H), 4.67 (t, 4H).13CNMR (100 MHz, CDCl 3 ), δ(TMS, ppm): 193.0,   80.4, 74.3, 71.0.Ferrocenedimethanol (5).In a 250 mL round-bottom flask was added 4 (3.63 g, 15 mmol) in dry methanol (100 mL).The solution was cooled to 0 o C and 1.70 g (45 mmol) of NaBH 4 was added portionwise.After the mixture was stirred at 0 o C for another 30 min and at room temperature for 2 h, acetic acid (2 mL) was added to quench the reaction.The reaction mixture was concentrated and then extracted with ethyl acetate.The organic phases were combined and dried over MgSO 4 overnight.The solution was heated at 50 o C for 3 h and then stirred at room temperature for 20 h.Afterward, the reaction mixture was diluted in 350 mL chloroform and washed with 100 mL of a saturated aqueous solution of sodium bicarbonate.Solid sodium S5 bicarbonate was Electronic Supplementary Material (ESI) for Polymer Chemistry This journal is © The Royal Society of Chemistry 2013 S17

Table S1
Electrochemical properties of the polymers Determined by CV analysis, where E pa is the potential of the anodic peak current and E pc is the potential of the cathodic current.b Formal redox potential E 1/2 = (E pa + E pc )/2.△E p = E pa  E pc . c