upporting Information pray Processable Green to Highly Transmissive Electrochromics via Chemically Polymerizable Donor-Acceptor Heterocyclic Pentamers Pierre M. Beaujuge, tefan Ellinger, John. eynolds* [ ] P. M. Beaujuge,. Ellinger, Prof. Dr. J.. eynolds The George and Josephine Butler Polymer esearch Laboratory Department of Chemistry Center for Macromolecular cience and Engineering University of Florida, Gainesville, FL, 3611 (UA) Fax: (+1) 35-39-971 E-mail: reynolds@chem.ufl.edu EXPEIMENTAL: All reagents and starting materials were purchased from commercial sources and used without further purification unless otherwise noted. The solvents were distilled and dried using known methods [1]. All reactions were done under argon atmosphere if not otherwise mentioned. 1 H NM and 13 C NM spectra were collected on a Mercury 300 MHz using CDCl 3 or C D Cl and were referenced to the solvent residual peak (CDCl 3 : 1 H: δ= 7.6 ppm, 13 C: δ= 77.3 ppm; C D Cl : 1 H: δ= 6.00 ppm). Elemental analyses were carried out by obertson Microanalytical Laboratories, Inc. or Atlantic Microlab, Inc. High resolution mass spectrometry was performed by the spectroscopic services at the Department of Chemistry of University of Florida with a Finnigan MAT 96Q mass spectrometer. Gel permeation chromatography (GPC) was performed using a Waters Associates GPCV000 liquid chromatography system with its internal differential refractive index detector (DI) at 0 o C, using two Waters tyragel H-5E columns (10 µm PD, 7.8 mm i.d., 300 mm length) with HPLC grade THF as the mobile phase at a flow rate of 1.0 ml / min. Injections were made at 0.05-0.07 % w/v sample concentration using a 0.5 µl injection volume. etention times were calibrated against narrow molecular weight polystyrene standards (Polymer Laboratories; Amherst, MA). Electrochemistry was performed using a three-electrode cell 1
with a platinum wire or a Pt flag as the counter electrode, a silver wire pseudo-reference electrode calibrated using a 5 mm solution of Fc/Fc + in 0.1 M electrolyte solution, and a platinum button or IT-coated glass slide (7 50 0.7 mm, 0 Ω cm -1 ) as the working electrode. The IT electrodes were purchased from Delta Technologies, Ltd. All potentials were reported vs Fc/Fc +. An EG&G Princeton Applied esearch model 73 potentiostat was used under the control of Corrware II software from cribner and Associates. All absorption spectra from square-wave potential step absorptometry and spectroelectrochemistry studies were performed using a Varian Cary 500 can UV-vis-near-I spectrophotometer. Colorimetry measurements were obtained using a Minolta C-100 Chroma Meter. The sample was illuminated from behind with a D50 (5000K) light source in a light booth designed to exclude external light. ynthesis and characterization. 1 H, NaH DMF = ctyl 1. n-buli, THF. nme 3 Cl 3 nme 3 3 + N N PdCl (PPh 3 ) THF FeCl 3, N Me CHCl 3 n N N N N 5 = ctyl, 6 3 + N N 7 PdCl (PPh 3 ) THF N N 8 FeCl 3, N Me CHCl 3 N N = ctyl, 9 n cheme 1. ynthesis of Pentamer A (5), Pentamer B (8), Polymer A (6) and Polymer B (9)
General conditions for the synthesis of 3,3-Bis-(octyloxymethyl)-3,-dihydro-Hthieno[3,-b][1,]dioxepine (): A 500 ml flame dried single-neck round bottom flask was filled with anhydrous DMF (50 ml), NaH (60% in mineral oil) (5.6 g, 10 mmol) and octan- 1-ol (1. g, 9 mmol). The mixture was heated at 90 C over a period of hours, then 3,3- bis(bromomethyl)-3,-dihydro-h-thieno[3,-b][1,]dioxepine [] (1) (8 g, 3. mmol) was added by portions to the hot reagent. After stirring overnight at 100 C, the reaction mixture was cooled down to room temperature, added to brine (700 ml) and extracted 3 times with ethyl ether (500 ml). The organic phase was washed with water, dried over magnesium sulfate and the solvent was removed affording a dark orange oil. The resulting oil was purified by column chromatography on silica with hexane/dichloromethane (3:) as eluent. The solvent was evaporated and compound was obtained as a clear oil (7 g, 68 %). 1 H NM (300 MHz, CDCl 3, δ): 6. (s,h),.01 (s, H), 3.8 (s, H), 3.0 (t, J = 6. Hz, H), 1.57-1.56 (m, H) 1.9-1.7 (m, 0H), 0.88 (t, J = 6.8 Hz, 6H); 13 C NM (75MHz, CDCl 3, δ): 19.9, 105., 73.9, 71.9, 69.8, 7.9, 3.1, 9.7, 9.6, 9.5, 6.3,.9, 1.3; HM (TF, m/z): [M+H] + calculated for C 5 H, 1.3033; found, 1.99. General conditions for the synthesis of 3,3-bis(octyloxymethyl)-3,-dihydro-Hthieno[3,-b][1,]dioxepine-6-yl)trimethyl-stannane (3): Compound (.1 g,.81 mmol) was dissolved in dry THF (17 ml) and cooled down to -78 C. A solution of n-butyllithium in hexanes (.51 ml, 6.6 mmol) was added over a hour period and the mixture was stirred for 1 hour. Trimethyltinchloride (6.3 ml, 6.3 mmol) was subsequently added, the mixture was allowed to warm up to room temperature and stirred for 16 hours. The solvent was evaporated affording a yellow-brown oil (.67 g, 9 %) which was used for the next step without further purification. 1 H NM (300 MHz, CDCl 3, δ): 6.70 (s, 1H), 3.98 (s, H), 3.93 (s, H), 3.8 (s, H), 3.39 (t, J = 6. Hz, H), 1.57-1.56 (m, H), 1.9-1.7 (m, 0H), 0.87 (t, J = 6.8 Hz, 6H), 0.3 (s, 9H). 3
,7-di(thiophen-yl)benzo[c][1,,5]thiadiazole: Tributyl(thiophen--yl)stannane (7.6 g, 0 mmol),,7-dibromobenzo[c][1,,5]thiadiazole [3] (.5 g, 8.33 mmol) and Pd(PPh 3 ) Cl (333 mg, mol %) were dissolved in THF (80 ml). The mixture was stirred for 36 hours at 60 C then the solvent was evaporated and the product was precipitated twice in MeH. After filtration through Büchner, an orange-red solid (1.85 g, 7 %) was collected. 1 H NM (300 MHz, CDCl 3, δ): 8.1 (dd, J = 0.9, 3.7 Hz, H), 7.83 (s, H), 7.5 (dd, J = 0.9,.9 Hz, H), 7.0 (dd, J = 0.9,.9 Hz, H); 13 C NM (75 MHz, CDCl 3, δ): 15.81, 139.57, 18., 17.7, 17.00, 16.15, 15.9; HM (TF, m/z): [M + ] calcd. for C 1 H 8 N 3, 300.99; found, 300.9936.,7-bis(5-bromothiophen-yl)benzo[c][1,,5]thiadiazole ():,7-di(thiophen-yl)benzo[c] [1,,5]thiadiazole (.5 g, 8.3 mmol) was dissolved in CHCl 3 (00 ml) and a catalytic amount of acetic acid. Then NB (. g,.97 mmol) was added portion wise and the mixture was stirred for 36 h at room temperature under light protection. The precipitate was filtered through Büchner, washed with copious amounts of water, methanol, acetone and the product was collected as an red solid (.75 g, 7 %). 1 H NM (300 MHz, CDCl 3, δ): 7.8 (d, (t, J = 3.9 Hz, H), 7.79 (s, H), 7.16 (d, (t, J = 3.9 Hz, H). 13 C NM could not be determined because of poor solubility; HM (TF, m/z): [M + ] calcd. for C 1 H 6 N 3, 56.8133; found, 56.8157..,7-bis(,3-dihydrothieno[3,-b][1,]dioxin-5-yl)benzo[c][1,,5]thiadiazole: (,3-dihydrothieno[3,-b][1,]dioxin-5-yl)trimethylstannane [] (11.58 g, 37.93 mmol),,7-dibromobenzo [c][1,,5]thiadiazole (3.99 g, 13.55 mmol) and Pd(PPh 3 ) Cl (380 mg, mol %) were dissolved in THF (00 ml). The mixture was stirred for 7 hours at 60 C, the solvent was evaporated and the product was precipitated twice in MeH. The dark-red solid was filtered through Büchner funnel and collected (3.63 g, 6%). 1 H NM (300 MHz, CDCl 3, δ): 8.38 (s, H), 6.56 (s, H),.0-.30 (m, 8H); 13 C NM (75 MHz, CDCl 3, δ): 15.58, 11.90, 10.9,
16.86, 13.93, 113.69, 10.19, 65.3, 6.58; HM (TF, m/z): [M + ] calcd. for C 18 H 1 N 3, 17.003; found, 17.0066.,7-bis(7-bromo-,3-dihydrothieno[3,-b][1,]dioxin-5-al) benzo[c] [1,,5] thiadiazole (7):,7-bis(,3-dihydrothieno[3,-b][1,]dioxin-5-yl)benzo[c][1,,5]thiadiazole (3.9 g, 8.38 mmol) was dissolved in CHCl 3 (800 ml) and a catalytic amount of acetic acid is added. Then NB (3.73 g, 0.95 mmol) was added portion wise and the mixture was stirred for 8 h at room temperature under light protection. The dark-red precipitate was filtered through Büchner, washed with water, methanol, acetone and the product was collected ( g, 83 %). 1 H NM (300 MHz, CDCl 3, δ): 8.35 (s, H),.39 (m, 8H); 13 C NM was not determined because of lack of solubility in common NM solvents; HM (TF, m/z): [M + ] calcd. for C 18 H 10 N 3, 57.8; found, 57.85. Pentamer A /,7-bis(5-(3,3-bis(octyloxymethyl)-3,-dihydro-H-thieno[3,- b][1,]dioxepin-6-yl)thiophen-yl)benzo[c][1,,5]thiadiazole (5): Compound 3 (. g, 6.97 mmol),,7-bis(5-bromothiophen-yl)benzo[c][1,,5]thiadiazole () (1.3 g,.81 mmol) and Pd(PPh 3 ) Cl (81 mg, mol %) were dissolved in THF (70 ml). The mixture was stirred for 8 hours at 60 C, the solvent was evaporated and the product was purified by column chromatography on silica with hexane/dichloromethane (:1) as eluent. The solvent was evaporated and compound 5 was obtained as a purple oil (.3 g, 70 %). 1 H NM (300 MHz, CDCl 3, δ): 8.10 (d, J = 3.8 Hz, H), 7.8 (s, H), 7.3 (d, J = 3.8 Hz, H), 6.0 (s, H),.3 (s, H),.08 (s, H), 3.57 (s, 8H), 3.3 (t, J = 6. Hz, 8H), 1,55 (m, 8H), 1.30 (m, 0H), 0.87 (t, J = 6.3 Hz 1H); 13 C NM (75MHz, CDCl 3, δ): 15.85, 150.7, 15.87, 138.18, 136.60, 18.0, 15.83, 15.33, 1.1, 117.33, 10.7, 7.3, 7.17, 7.03, 69.93, 8.11, 3.10, 9.81, 9.68, 9.5, 6.1,.90, 1.3; HM (TF, m/z): [M+H] + calcd. for C 6 H 9 N 8 5, 1177.5530; found, 1177.557. Anal. calcd. for C 6 H 9 N 8 5 : C 65.7, H 7.87, N.38; found: C 65.78, H 8.03, N.3. 5
Pentamer B /,7-bis(7-(3,3-bis(octyloxymethyl)-3,-dihydro-H-thieno[3,- b][1,]dioxepin-6-yl)-,3-dihydrothieno[3,-b][1,]dioxin-5-yl)benzo[c][1,,5]thiadiazole (8): Compound 3 (.8 g, 7.09 mmol),,7-bis(7-bromo-,3-dihydrothieno[3,-b][1,]dioxin- 5-yl)benzo[c] [1,,5]- thiadiazole (7) (1.68 g,.95 mmol) and Pd(PPh 3 ) Cl (85 mg, mol %) were dissolved in THF (70 ml). The mixture was stirred for 8 hours at 60 C, the solvent was evaporated and the product was purified by column chromatography on silica with hexane/dichloromethane (:1) as eluent. The solvent was evaporated and compound 8 was obtained as a dark blue tacky solid (1.08 g, 9 %). 1 H NM (300 MHz, CDCl 3, δ): 8.3 (s, H), 6.5 (s, H),.1 (s, 8H).5 (s, H),.08 (s, H), 3.60 (m, 8H), 3.3 (t, J = 6. Hz, 8H), 1,55 (m, 8H), 1.30 (m, 0H), 0.87 (t, J = 6.3 Hz, 1H); 13 C NM (75MHz, CDCl 3, δ): 15.63, 19.8, 15.9, 10.07, 137.61, 16.86, 13.65, 115.1, 113.08, 11.5, 103.69, 7.71, 7.3, 7.0, 70.1, 65.15, 69, 8.09, 3.08, 9.81, 9.68, 9.5, 9.0,.88, 1.31; HM (MALDI TF, m/z): [M + ] calcd. for C 68 H 96 N 1 5, 19.5561; found, 19.5557. Anal. calcd. for C 68 H 96 N 1 5 : C 63.13, H 7.8, N.17; found: C 63.3, H 7.50, N.1. Polymer A / (6): Compound 5 (59 mg, 0.39 mmol) was dissolved in chloroform (70 ml). A solution of FeCl 3 (316 g, 1.95 mmol, 5eq) in nitromethane was added to the stirred monomer at room temperature. The dark purple monomer solution turned dark green with addition of oxidizing agent. The mixture was stirred 8 hours at room temperature. It was then precipitated into methanol (500 ml). The precipitate was filtered, redissolved in chloroform (300 ml) and stirred for 6 hours with hydrazine monohydrate (6 ml). After concentration by evaporation, the polymer solution (green) was precipitated into methanol (500 ml), the precipitate was filtered through a oxhlet thimble and purified via oxhlet extraction for 8h with methanol. The polymer was extracted with chloroform for 6 hours, the solvent was evaporated, the polymer was precipitated in methanol and collected as a black solid (0 mg, 88 %). 1 HNM (300 MHz, C D Cl (100 C), δ): 8.16 (bs, H), 7.89 (bs, H), 7.3 (bs, H), 6
.3 (bs, 8H), 3.7-3.56 (m, 16H), 1.69 (bs, 8H), 1.38 (bs, 0H), 0.96 (bs, 1H). GPC analysis: ee Table 1. Anal. calcd for C 6 H 90 N 8 5 : ee Table 1. Polymer B / (9): Compound 8 (578 mg, 0.5 mmol) was dissolved in chloroform (70 ml). Following the procedure described for synthesizing polymer A (6), polymer B (9) was obtained as a black solid (80 mg, 83 %). 1 HNM (300 MHz, C D Cl (100 C), δ): 8.0 (bs, H),.50 (bs, 8H),.8 (bs, 8H), 3.70 (bs, 8H), 3.55 (bs, 8H), 1.55-0.93 (m, 60H). GPC analysis: ee Table 1. Anal. calcd for C 68 H 9 N 1 5 : ee Table 1. Table 1. GPC Estimated Molecular Weights in THF, Elemental Analysis of the Polymers 7
Absorbance (a.u.).5.0 1.5 1.0 0.5 Trimer A (310nm, 6nm) Trimer B (3nm, 81nm) Pentamer A (366nm, 5nm) Pentamer B (385nm, 558nm) 0.0 56nm 61nm 76nm 77nm 300 350 00 50 500 550 600 650 700 750 Wavelength (nm) Figure 1. olution optical absorbance of Trimer A, Trimer B, Pentamer A and Pentamer B in Toluene (pectrum of each system is normalized at the longer wavelength absorption maximum). Legend specifies the values of the respective absorption maxima for both high (blue) and low energy (red) absorption bands. 8
6 I(mA/cm ) 0 - - -6-0.6-0. -0. 0.0 0. 0. 0.6 0.8 1.0 1. E(V) vs. Fc/Fc + Figure. Cyclic voltammetry of a thin film of Polymer A drop-cast on a Pt button electrode (9 scans). Electrochemical oxidation of the films was carried out in 0.1 M LiBF /ACN supporting electrolyte using a silver wire as a quasi-reference electrode (calibrated against Fc/Fc + ) and a platinum flag as the counter electrode. 3 I(mA/cm ) 1 0-1 - -3 - -0. -0. 0.0 0. 0. 0.6 0.8 E(V) vs. Fc/Fc + Figure 3. Differential Pulse Voltammetry of a thin film of Polymer A drop-cast on a Pt button electrode. Electrochemical oxidation of the films was carried out in 0.1 M LiBF /ACN supporting electrolyte using a silver wire as a quasi-reference electrode (calibrated against Fc/Fc + ) and a platinum flag as the counter electrode. 9
8 6 I(mA/cm ) 0 - - -0.8-0.6-0. -0. 0.0 0. 0. 0.6 0.8 1.0 1. 1. E(V) vs. Fc/Fc + Figure. Cyclic voltammetry of a thin film of Polymer B drop-cast on a Pt button electrode (9 scans). Electrochemical oxidation of the films was carried out in 0.1 M LiBF /ACN supporting electrolyte using a silver wire as a quasi-reference electrode (calibrated against Fc/Fc + ) and a platinum flag as the counter electrode. 10 8 6 I(mA/cm ) 0 - - -0.6-0. -0. 0.0 0. 0. 0.6 0.8 1.0 E(V) vs. Fc/Fc + Figure 5. Differential Pulse Voltammetry of a thin film of Polymer B drop-cast on a Pt button electrode. Electrochemical oxidation of the films was carried out in 0.1 M LiBF /ACN supporting electrolyte using a silver wire as a quasi-reference electrode (calibrated against Fc/Fc + ) and a platinum flag as the counter electrode. 10
Table. quare-wave potential stepping electrochromic switching of spray-cast Polymer A onto IT in 0.1 M LiBF /propylene Carbonate solution switching between -0.5 V and +1.05 V (vs. Fc/Fc + ) with a switch time of s. Cycle [a] T (%) [b] Q (mc/cm ) [c] CE (cm /C) [d] %Decay [e] 1 3.6.7 16 0 100 50 500 750 1000 3.1 3 33.8 33. 3.7.77.71.6.6.55 [a] Complete cycle is s [b] % ptical change in transmittance at 67 nm [c] Injected/ejected charge per unit area of spray-cast film [d] CE = D/Q = log(%t ox /%T red )/Q [e] % Loss of electrochromic contrast (% decay in T). 11 13 1 1 13 1.5 1.7.3 3.5 5.5 [1] W. L. F. Armarego, C. L. L. Chai, Purification of Laboratory Chemicals, 5th Edition, ELEVIE, 003. [] B. D. eeves, C.. G. Grenier, A. A. Argun, A. Cirpan, T. D. McCarley, J.. eynolds, Macromolecules 00, 37, 7559. [3]. Admassie,. Inganas, W. Mammo, E. Perzon, M.. Andersson, ynth. Met. 006, 156, 61. [] C. Edder, J. M. J. Frechet, rg. Lett. 003, 5, 1879. 11