Supporting Information

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1 Supporting Information Controlled Self-Assembly of Asymmetric Dumbbell-Shaped Rod Amphiphiles: Transition from Toroids to Planar Nets Eunji Lee, Young-Hwan Jeong, Jung-Keun Kim, Myongsoo Lee* Center for Supramolecular Nano-Assembly and Department of Chemistry, Yonsei University, Seoul , Korea. Materials and Methods Materials 3-Chloro-2-chloromethyl-1-propene (96 %) from Acros, p-toluene-sulfonyl chloride (98 %) from Junsei and tetrakis(triphenylphosphine) palladium(0) (99 %), 4,4'- bis(bromomethyl)biphenyl (95 %), 4-bromo-4'-hydroxybiphenyl (99 %) from TCI were used as received. Triethylene glycol monomethyl ether (95 %), ethanol (99.5 %), hexyl alcohol (99 %), decyl alcohol (98 %), tetradecyl alcohol (98 %), 9-BBN (0.5 M solution in THF), 1,3,5-tribromobenzene (99 %), n-butyllithium (1.6 M solution in n-hexane), 4- bromoanisole (99 %), borane-thf complex (1.0 M solution in THF), triisopropyl borate (98 %) from Aldrich and the conventional reagents were used as received. All atmosphere sensitive reactions were done under nitrogen. Dry THF was obtained by distilled from sodium and benzophenone. Visualization was accomplished with UV light and iodine vapor. Flash chromatography was carried out with silica gel 60 ( mesh) from EM Science. General 1 H-NMR was recorded from CDCl 3 solutions on Bruker 250 NMR spectrometers. The purity of the products was checked by thin layer chromatography

2 (TLC; Merck, silica gel 60). Microanalyses were performed with a Perkin Elmer 240 elemental analyzer at Organic Chemistry Research Center. MALDI-TOF mass spectroscopy (MALDI-TOF-MS) was performed on a Perseptive Biosystems Voyager- DE STR using a 2, 5-dihydroxy benzoic acid as matrix. Recycling preparative high performance liquid chromatography (HPLC) was performed at room temperature using a 20 mm 600 mm poly styrene column on a Japan Analytical Industry Model LC-908 recycling preparative HPLC system, equipped with UV detector 310 and RI detector RI- 5. Chloroform (HPLC grade) was used as eluent. The transmission electron microscope (TEM) was performed at 120 kv using JEM Optical absorption spectra were obtained from a Shimadzu 1601 UV spectrometer. Synthesis The synthesis procedures used in the preparation of dumbbell-shaped molecules are described in scheme 2. Synthesis of compound 3 and 4 The synthesis of compounds 3 and 4 was performed according to the procedures reported previously. S1 3; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 7Ar-H), 7.00 (d, 4Ar-H, o to ArO, J = 7.5 Hz). 4; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 7Ar-H), 6.96 (d, 4Ar-H, o to ArO, J = 8.7 Hz), 4.02 (d, 4H, Ar-OCH 2, J = 5.4 Hz), (m, 128H, -OCH 2 ), 3.35 (s, 24H, -OCH 3 ), (m, 6H, -CH(OCH 2 ) 2 ). Synthesis of compound 5 4-(tert-butyldimethylsilyloxy)-biphenyl-4 -boronic acid (155 mg, 0.56 mmol) and compound 4 (675 mg, 0.33 mmol) were dissolved in degassed THF (150 ml). Degassed 2.0 M aqueous Na 2 CO 3 (70 ml) was added to the solution and then tetrakis- (triphenylphosphine) palladium(0) (12 mg, 0.01 mmol) was added. The mixture was heated at reflux for 24 hours with vigorous stirring under nitrogen. Cooled to room temperature, the layers were separated then the aqueous layer was washed twice with dichloromethane. The combined organic layer was dried over anhydrous magnesium sulfate and filtered. The solvent was removed in a rotary evaporator, and the crude

3 product was purified by column chromatography (silica gel) using methanol : ethyl acetate =1 : 5 as eluent to yield 400 mg (55 %) of colorless liquid. 5; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar-H, o to ArO), 4.02 (d, 4H, Ar-OCH 2, J = 4.7 Hz), (m, 128H, -OCH 2 ), 3.31 (s, 24H, -OCH 3 ), (m, 6H, -CH(OCH 2 ) 2 ). Synthesis of compound 6 Compound 5 (400 mg, 0.18 mmol), 4,4'-bis(bromomethyl)biphenyl (620 mg, 1.8 mmol) and excess K 2 CO 3 were dissolved in 150 ml of acetone. The mixture was heated at reflux for 1 day and then cooled to room temperature. The solvent was removed in a rotary evaporator, and the resulting mixture was poured into water and extracted with dichloromethane. The dichloromethane solution was washed with water, dried over anhydrous magnesium sulfate, and filtered. After the solvent was removed in a rotary evaporator, the crude products were purified by column chromatography (silica gel) using ethyl acetate : methanol as eluent to yield 300 mg (68 %) of a colorless liquid. 6; 1 H-NMR (250MHz, CDCl 3, ppm) : E = (m, 21Ar-H), (m, 6Ar-H, o to ArO), 5.15 (s, 2H, -phenylch 2 OH), 4.53 (s, 2H, -phenylch 2 Br), 4.05 (d, 4H, Ar- OCH 2, J = 4.0 Hz), (m, 128H, -OCH 2 ), 3.34 (s, 24H, -OCH 3 ), (m, 6H, -CH(OCH 2 ) 2 ). Synthesis of compound 7 Compound 7 was synthesized by etherification reaction of compound 5 with 1, 12-dibromododecane. 7; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar-H, o to ArO), (m, 6H, Ar-OCH 2 ), (m, 154H, -OCH 2 ), (m, 6H, -CH(OCH 2 ) 2 ), (m, 4H, -OCH 2 CH 3 ), (m, 16H, -CH 2 ). Synthesis of compound 8a, 8b, 8c and 8d The synthesis of compounds 8a-8d were performed according to the procedures reported previously with second-generation dendritic alkyl coils. S2 8a; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar- H, o to ArO), 4.10 (d, 4Ar-H, Ar-OCH 2, J = 5.6 Hz), (m, 48H, -OCH 2 ), 2.23-

4 2.04 (m, 6H, -CH(OCH 2 ) 2 ), 1.19 (t, 24H, -CH 2 CH 3 ). 8b; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar- H, o to ArO), 4.09 (d, 4Ar-H, Ar-OCH 2, J = 5.6 Hz), (m, 48H, -OCH 2 ), (m, 6H, -CH(OCH 2 ) 2 ), (m, 64H, -CH 2 ), 0.90 (t, 24H, -CH 2 CH 3 ). 8c; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar- H, o to ArO), 4.09 (d, 4Ar-H, Ar-OCH 2, J = 5.4 Hz), (m, 48H, -OCH 2 ), (m, 6H, -CH(OCH 2 ) 2 ), (m, 128H, -CH 2 ), 0.90 (t, 24H, -CH 2 CH 3 ). 8d; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 13Ar-H), (m, 6Ar- H, o to ArO), 4.07 (d, 4Ar-H, Ar-OCH 2, J = 5.4 Hz), (m, 48H, -OCH 2 ), (m, 6H, -CH(OCH 2 ) 2 ), (m, 192H, -CH 2 ), 0.88 (t, 24H, -CH 2 CH 3 ). Synthesis of rod amphiphiles 1a, 1b, 1c and 1d Compounds 1a-1d were synthesized using the same procedure. A representative example is described for compound 1a. Compounds 6 (300 mg, 0.13 mmol), 8a (260 mg, 0.19 mmol) and excess K 2 CO 3 were dissolved in 100 ml of acetone. The mixture was heated at reflux for 24 hours and then cooled to room temperature. The solvent was removed in a rotary evaporator, and the resulting mixture was poured into water and extracted with dichloromethane. The dichloromethane solution was washed with water, dried over anhydrous magnesium sulfate, and filtered. After the solvent was removed in a rotary evaporator, the crude products were purified by column chromatography (silica gel) using ethyl acetate : methanol as eluent, and the product was further purified by recycling preparative HPLC to yield 230 mg (48 %) of a colorless waxy solid. 1a; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 34Ar-H), (m, 12Ar- H, o to ArO), 5.17 (s, 4H, -phenylch 2 OAr), 4.07 (m, 8Ar-H, Ar-OCH 2 ), (m, 200H, -OCH 2 ), (m, 12H, -CH(OCH 2 ) 2 ), 1.16 (t, 24H, -CH 2 CH 3 ); Anal. Calcd for: C 194 H 294 O 54 ; C, 66.76; H, 8.49, Found : C, 66.62; H, 8.59; Calcd MALDI-TOF-MS m/z ([M+Na] + ), Found b; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 34Ar-H), (m, 12Ar- H, o to ArO), 5.18 (s, 4H, -phenylch 2 OAr), 4.07 (m, 8Ar-H, Ar-OCH 2 ), (m, 200H, -OCH 2 ), (m, 12H, -CH(OCH 2 ) 2 ), (m, 64H, -CH 2 ), 0.87 (t,

5 24H, -CH 2 CH 3 ); Anal. Calcd for: C 226 H 358 O 54 : C, 68.91; H, 9.16, Found : C, 68.86; H, 9.20; Calcd MALDI-TOF-MS m/z ([M+Na] + ), Found c; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 34Ar-H), (m, 12Ar- H, o to ArO), 5.18 (s, 4H, -phenylch 2 OAr), 4.07 (m, 8Ar-H, Ar-OCH 2 ), (m, 200H, -OCH 2 ), (m, 12H, -CH(OCH 2 ) 2 ), (m, 128H, -CH 2 ), 0.87 (t, 24H, -CH 2 CH 3 ); Anal. Calcd for: C 258 H 422 O 54 : C, 70.62; H, 9.69, Found : C, 70.76, H, 9.65; Calcd MALDI-TOF-MS m/z ([M+Na] + ), Found d; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 34Ar-H), (m, 12Ar- H, o to ArO), 5.18 (s, 4H, -phenylch 2 OAr), 4.07 (m, 8Ar-H, Ar-OCH 2 ), (m, 200H, -OCH 2 ), (m, 12H, -CH(OCH 2 ) 2 ), (m, 192H, -CH 2 ), 0.87 (t, 24H, -CH 2 CH 3 ); Anal. Calcd for: C 290 H 486 O 54 : C, 72.01; H, 10.13, Found; C, 71.73; H, 10.20; Calcd MALDI-TOF-MS m/z ([M+Na] + ), Found Synthesis of rod amphiphiles 2 The dumbbell-shaped compound 2 prepared according to the same procedures of 1a-1d. Compound 2 was synthesized by etherification reaction of compound 7 with an excess of compound 8c. 2; 1 H-NMR (250 MHz, CDCl 3, ppm) : E = (m, 26Ar-H), (m, 12Ar- H, o to ArO), (m, 12H, Ar-OCH 2 ), (m, 200H, -OCH 2 ), (m, 12H, -CH(OCH 2 ) 2 ), (m, 4H, -OCH 2 CH 3 ), (m, 144H, -CH 2 ), 0.87 (t, 24H, -CH 2 CH 3 ); Anal. Calcd for: C 256 H 434 O 54 : C, 70.26; H, 10.00, Found : C, 70.22; H, 9.98; Calcd MALDI-TOF-MS m/z ([M+Na] + ), Found

6 Solution Preparation Aqueous solutions of compounds 1a-1d and 2 were prepared by mixing molecules and deionized water in clean glass vials (25 ml). The samples were sealed with para film at room temperature. Before using in each experiment they were stirred 3 days and stabilized more than a week, except TEM study with controlling temperature which solutions were prepared at temperature mentioned in procedure. Fluorescence Microscopy Experiments The fluorescence microscopic images were obtained with Nikon Eclipse TE2000-U, inverted fluorescence microscope equipped with DXM1200C digital camera, using a super high pressure mercury lamp (100 W) as a light source and a UV-2A filter. 5 OL of the dilute solutions (0.01 wt %) of 1c and 1d were deposited onto a glass slide and a cover glass was placed over the sample before observation. LCST Measurements Lower critical solution temperatures (LCSTs) of polymer suspensions were determined as an onset of the transmittance decrease with increasing temperature. The optical transmittances of aqueous solutions at various temperatures were recorded at wavelength of 500 nm with a Shimadzu 1601 UV-vis spectrometer (Kyoto, Japan). The sample quartz cell was thermostated with an external water bath of a Daehan Scientific precision digital refrigerated circulator (Seoul, Korea). The rate of temperature increase was 0.3 C / min. At each temperature, the solutions were equilibrated for 10 minutes. NMR Experiments 1 H NMR (400 MHz) spectra were recorded on a thermoregulated Bruker Avance 400 using a solution of molecule 1b in D 2 O (99.9 D atom %) with a concentration of 0.03 wt %. At each temperature, the solution was equilibrated for 10 minutes before data acquisition. The dehydration of the hydrophilic coil segment of molecule 1b at different temperature was supported by variable temperature 1 H spectroscopy study. The position of 1,4-dioxane peak was used as reference.

7 TEM Experiments Transmission electron microscopy observation was carried out with a JEOL JEM-2010 operated at 120 kv. For study of structure of dumbbell-shaped molecule in aqueous solution, a drop of aqueous solution of dumbbell-shaped molecule ( wt %) was placed on a carbon-coated copper grid and allowing the solution to evaporate under ambient conditions. The samples were stained by depositing a drop of uranyl acetate aqueous solution (2 wt %) onto the surface of the sample-loaded grid. The cryogenic transmission electron microscopy experiments (cryo-tem) were performed with a thin film of aqueous solution of dumbbell-shaped molecule (5 OL) transferred to a lacey supported grid. The thin aqueous films were prepared under controlled temperature and humidity conditions (97-99 %) within a custom-built environmental chamber in order to prevent evaporation of water from sample solution. The excess liquid was blotted with filter paper for 2-3 seconds, and the thin aqueous films were rapidly vitrified by plunging them into liquid ethane (cooled by liquid nitrogen) at its freezing point. To investigate the effect of temperature, solution were sealed with Teflon tape and elevated the desired temperature in Daehan Scientific precision digital refrigerated circulator having an accuracy ± 0.1 o C. The system was maintained for 1 hour. And then solution was placed on the lacey supported grid, and thin aqueous films were quickly quenched in liquid ethane. The grid was transferred, on a Gatan 626 cryoholder, using a cryo-transfer device. After that they were transferred to a JEM-2010 TEM. Direct imaging was carried out at a temperature of approximately o C and with a 120 kv accelerating voltage, using the images acquired with a Dual vision 300W and SC 1000 CCD camera (Gatan, Inc.; Warrendale, PA)

8 Figure S1. Changes in the absorption spectra of dumbbell-shaped amphiphiles in aqueous solution (0.01 wt %) with increasing the alkyl chain in length. Figure S2. 1 H-NMR spectra of 1b (a) in CDCl 3 and (b) in D 2 O (0.03 wt %). S3

9 Figure S3. Changes in the Fluorescence spectra of 1b in aqueous solution with temperature variation (0.01 wt %). Figure S4. (a, b) TEM images (negatively stained with uranyl acetate) and (c, d) cryo- TEM images of nanorings of 1b in aqueous solution (0.01 wt %).

10 Figure S5. (a, b) TEM images (negatively stained with uranyl acetate) and (c) cryo- TEM image of a 2-D network structure of 1c in aqueous solution (0.01 wt %). Figure S6. Cryo-TEM images of a hollow vesicular structure of 1d in aqueous solution (0.01 wt %).

11 Influence of concentration on the aggregation structure of 1b and 1c Figure S7. TEM images of films cast from 0.1wt % solutions of (a) 1b and (b) 1c, (inset) high magnification, scale bar is 100 nm. Cryo-TEM images of 0.1 wt % aqueous solutions of (c) 1b and (d) 1c. These results indicate that the self-assembled structures remain unchanged within the investigated concentration range ( wt %).

12 Temperature induced structural change of 1b Figure S8. Structural change on heating of 1b in aqueous solution (0.01 wt %). (a) TEM image of cast film at 70 o C. Cryo-TEM images (b) at 50 o C and (c, d) at 70 o C. This result indicates that the toroidal structure transforms into 2-D networks, on heating.

13 Structural progression of the 2-D nets on cooling Figure S9. After heating to 70 o C, then equilibrated 1 hour to form 2-D networks (Figure S6), the solution of 1b was slowly cooled to room temperature. (a) After 1 hour, the network shows to be loosened, (b) that separated into small fragments of fused rings within 1day. (c) Eventually, the structure changes into discrete toroids after 1 week.

14 References for Supporting Information S1. Jang, C.-J.; Ryu, J.-H.; Lee, J.-D.; Sohn, D.; Lee, M. Chem. Mater. 2004, 16, S2. Kim, J.-K.; Lee, E.; Jeong, Y.-H.; Lee, J.-K.; Zin, W.-C.; Lee, M. J. Am. Chem. Soc. 2007, 129, S3. a) Gitsov, I.; Fréchet, J. M. J. J. Am. Chem. Soc. 1996, 118, b) Liu, M.; Kono, K.; Fréchet, J. M. J. J. Controlled Release 2000, 65,