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1 1 Supporting Information Practical One-Step Synthesis of Symmetrical Liquid Crystalline Dialkyloligothiophenes for Molecular Electronic Applications Julie Leroy, Jeremy Levin, Sergey Sergeyev, and Yves Geerts* Laboratory of Polymer Chemistry, Université Libre de Bruxelles, Boulevard du Triomphe, CP 206/01, 1050 Brussels, Belgium (Received November 4, 2005; CL ; Copyright C The Chemical Society of Japan

2 Supporting Information Practical One-Step Synthesis of Symmetrical Liquid Crystalline Dialkyloligothiophenes for Molecular Electronic Applications Julie Leroy, Jeremy Levin, Sergey Sergeyev, and Yves Geerts* Laboratory of Polymer Chemistry, Université Libre de Bruxelles, Boulevard du Triomphe, CP 206/01, 1050 Brussels, Belgium General. All chemicals were purchased from Aldrich or Acros and used without further purification unless stated otherwise. All reactions were performed under dry Ar in oven-dry glassware using septum and syringe technique. THF was refluxed over sodium and benzophenone until blue-violet color persisted and distilled directly into reaction flask. Commercially available solution of n-buli in hexane was titrated with Ph 2 CHCOOH immediately before use. 1 H-NMR (300 MHz) and 13 C-NMR (75 MHz) spectra were recorded in CDCl 3 on Brucker Avance 300 spectrometer; chemical shifts (δ) are given in ppm relative to TMS (internal standard); coupling constants (J) are given in Hz. EI-MS (70 ev) specta were recorded on a VG Micromass 7070F instrument. Phase transition temperatures were measured by differential scanning spectroscopy (Mettler Toledo DSC 821). Optical textures were observed with polarizing microscope (Nikon Eclipse 80i). UV-Vis spectra were recorded on a Hewlett-Packard 8453 spectrophotometer. Alkylation of terthiophene (General procedure): A solution of 2,2 :5,2 -terthiophene 5 (500 mg, 2.12 mmol) in 10 ml of dry THF was cooled to 78 C, and a solution of n-buli (ca. 1.6M in hexane, 6.04 mmol) was added dropwise via cannula. The reaction mixture was stirred for 10 min at 78 C, then solution of t-buok (1.0 M in THF, 8.05 mmol) in THF was added. The stirring was continued for 15 min at 78 C, then the 1-haloalkane (4.24 mmol) was added.the reaction mixture was allowed to slowly reach room temperature and stirred overnight, quenched by slow addition of water (10 ml) and extracted with hexane (3 10 ml). The organic phase was dried with MgSO 4, volatile materials were removed in vacuum, and the solid residue was either crystallized from methanol/toluene or purified by column chromatography on SiO 2 (details are given for individual compounds).

3 5,5 -Dioctyl-2,2 -bithiophene 1. Prepared according to the general procedure from bithophene (250 mg, 1.5 mmol) and 1-iodooctane (0.51 ml). The crude product was purified first by flash chromatography (hexane/toluene 9:1) and then by crystallization from methanol/toluene. Yellow solid, yield g (93%). M.p. 43 C. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.89 (d, J = 3.5 Hz, 2 H), 6.65 (d, J = 3.5Hz, 2 H), 2.77 (t, J =7.5, 4 H), 1.67 (quint, J =7.7, 4 H), (m, 20 H), 0.88 (t, J = 6.8, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 144.7, 135.3, 124.5, 122.6, 31.9, 31.6, 30.1, 29.3, 29.2, 29.1, 22.6, 14.1 ppm. EI-MS: m/z (%): 390 ([M + ]). HR-EI-MS: calcd for C 24 H 38 S 2 ([M + ]): ; found: UV-Vis : λ max = 315 nm (ε = L cm -1 mol -1 ). 5,5 -Dihexyl-2,2 :5,2 -terthiophene 2a: Prepared according to the general procedure from 1-iodohexane (0.59 ml). Yellow solid, yield 0.750g (85%). Analytically pure sample was crystallized from methanol/toluene. DSC: K 51 C SmG 80 C I. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.97 (s, 2 H), 6.95 (d, J = 3.5 Hz, 2 H), 6.67 (d, J = 3.5 Hz, 2 H), 2.78 (t, J = 7.6, 4 H), 1.68 (quint, J = 7.3, 4 H), (m, 12 H), 0.89 (t, J = 6.9, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.4, 136.1, 134.6, 124.7, 123.4, 123.1, 31.6 (4 C), 30.2, 28.7, 22.6, 14.1 ppm. EI-MS: m/z (%):416 ([M + ]). HR-EI-MS: calcd for C 24 H 32 S 3 ([M + ]): ; found: UV-Vis: λ max 363 nm (ε = L cm -1 mol -1 ). 5,5 -Diheptyl-2,2 :5,2 -terthiophene 2b: Prepared according to the general procedure from 1-iodoheptane (0.65 ml). Yellow solid, yield g (80%). Analytically pure sample was crystallized from methanol/toluene. DSC: K 52 C SmG 79 C SmF 84 C SmC 90 C. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.97 (s, 2 H), 6.95 (d, J = 3.6 Hz, 2 H), 6.66 (d, J = 3.6 Hz, 2 H), 2.78 (t, J = 7.5 Hz, 4 H), 1.68 (quint, J=7.7 Hz, 4 H), (m, 16 H), 0.89 (t, J = 6.9 Hz, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.4, 136.1, 134.6, 124.7, 123.4, 123.1, 31.7, 31.6, 30.2, 29.0 (4C), 22.6, 14.1 ppm. EI-MS: m/z (%):444 ([M + ]). HR-EI- MS: calcd for C 26 H 36 S 3 ([M + ]): ; found: UV-Vis: λ max = 363 nm (ε = L cm -1 mol -1 ). 5,5 -Dioctyl-2,2 :5,2 terthiophene 2c: Prepared according to the general procedure from 1-iodooctane (0.73 ml). Yellow solid, yield g (85%). Analytically pure sample was crystallized from methanol/toluene. DSC: K 64 C SmG 70 C SmF 85 C SmC 90 C. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.97 (s, 2 H), 6.95 (d, J = 3.5, 2 H), 6.67 (d, J = 3.5 Hz, 2 H),

4 2.78 (t, J = 7.5 Hz, 4 H), 1.68 (quint, J =7.2 Hz, 4 H), (m, 20 H), 0.88 (t, J = 6.9 Hz, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.4, 136.1, 134.6, 124.8, 123.4, 123.1, 31.8, 31.6, 30.2, 29.3, 29.2, 29.1, 22.7, 14.1 ppm. EI-MS: m/z (%):472 ([M + ]). HR-EI- MS: calcd for C 28 H 40 S 3 ([M + ]): ; found: UV-Vis : λ max = 363 nm (ε = L cm -1 mol -1 ). 5,5 -Dinonyl-2,2 :5,2 -terthiophene 2d: Prepared according to the general procedure from 1-iodononane (0.84 ml). Yellow solid, yield g (85%). Analytically pure sample was crystallized from methanol/toluene. DSC: K 68 C SmF 92 C SmC 99 C I. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.97 (s, 2 H), 6.95 (d, J =3.6 Hz, 2 H), 6.66 (d, J =3.6 Hz, 2 H), 2.78 (t, J =7.5 Hz, 4 H), 1.68 (quint, J =7.7 Hz, 4 H), (m, 24 H), 0.89 (t, J = 6.9 Hz, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.4, 136.1, 134.6, 124.7, 123.4, 123.1, 31.9, 31.6, 30.2, 29.5, 29.4, 29.3, 29.1, 22.7, 14.1 ppm. EI-MS: m/z (%): 500 ([M + ]). HR-EI- MS: calcd for C 30 H 44 S 3 ([M + ]): ; found: UV-Vis : λ max = 363 nm (ε = L cm -1 mol -1 ). (±)-(R,S/S,R)- and (±)-(S,S/R,R)-5,5 -Di(3,7-dimethyloctyl)-2,2 :5,2 -terthiophene 2e, mixture of diastereoisomers. Prepared according to the general procedure from (±)-1- bromo-3,7-dimethyloctane (0.860 ml). Yellow solid, yield g (88%). Analytically pure sample was crystallized from methanol/toluene. M.p. 45 C. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 6.96 (s, 2 H), 6.95 (d, J =3.6 Hz, 2 H), 6.67 (d, J =3.6 Hz,2 H), (m, 4 H), (m, 2 H), (m, 4 H), (m, 14 H), 0.92 (d, J =2.5 Hz, 3 H), 0.88 (d, J =2.5Hz, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.6, 136.1, 134.6, 124.6, 123.4, 123.1, 39.3, 38.7, 37.0, 32.3, 27.9, 27.8, 24.7, 22.7, 22.6, 19.5 ppm. EI-MS: m/z (%): 528 ([M + ]). HR-EI-MS: calcd for C 32 H 48 S 3 ([M + ]): ; found: UV-Vis : λ max = 363 nm (ε = L cm -1 mol -1 ). 5,5 -Dioctyl-2,2,5,2,5,2 -quaterthiophene 3: Prepared as described for the terthiophenes 2 with the following amendment: quaterthiophene (500mg, 1.5mmol) was dissolved in 50ml of dry THF and reacted with BuLi (4.5 mmol), t-buok (6 mmol) and 1- iodooctane (3 mmol, 0.61 ml). Yellow solid, yield g, 82%. Analytically pure sample was crystallized from methanol/toluene. DSC : K 82 C Sm 158 C I. 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 7.03 (d, J = 3.7 Hz, 2 H), (2 overlapped d, 4 H), 6.68 (d, J = 3.3

5 Hz, 2 H), 2.79 (t, J = 7.5 Hz, 4 H), 1.68 (quint, J = 6.9, 4 H), (m, 20 H), 0.88 (t, J = 6.3, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 145.6, 136.7, 135.3, 134.4, 124.8, 124.0, 123.5, 123.3, 31.8, 31.6, 30.2, 29.3, 29.2, 29.1, 22.6, 14.1 ppm. EI-MS: m/z (%): 444 ([M + ]). HR-EI-MS: calcd for C 32 H 42 S 4 ([M + ]): ; found: UV-Vis: λ max = 395 nm (ε = L cm -1 mol -1 ). (±)-5-(3,7-Dimethyloctyl)thiophene 8c: Prepared according to the general procedure from thiophene (7) (250 mg, 2.98mmol) and (±)-1-bromo-3,7-dimethyloctane (0.634ml, 2.98mmol). The crude product was purified by flash chromatography (hexane/toluene 9:1) to give pale yellow oil. Yield g (95%). 1 H NMR (300 MHz, CDCl 3, 25 C): δ = 7.11 (dd, J = 5.1, J = 1.1, 1 H), 6.94 (dd, J = 3.3Hz, J= 1.8, 1 H), 6.80 (d, J= 2.6, 1 H), (m, 2 H), (m, 2 H), (m, 2 H), (m, 6 H), 0.92 (d, J =2.5 Hz, 3 H), 0.88 (d, J =2.5Hz, 6 H) ppm. 13 C NMR (75 MHz, CDCl 3, 25 C): δ = 146.1, 126.6, 123.7, 122.6, 39.3, 39.1, 37.1, 32.3, 27.9, 27.5, 24.7, 22.7, 22.6, 19.5 ppm. EI-MS: m/z (%): 224 ([M + ]); HR-EI-MS: calcd for C 14 H 24 S ([M + ]): ; found: UV-Vis: λ max = 235 nm (ε = 6500 L cm -1 mol -1 ).