Supporting Information
Two-component self-assembly with solvent leading to “wet” and microcrystalline organogel fibers
Miika Löfman*, Manu Lahtinen, Kari Rissanen, Elina Sievänen*
Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland.
* Corresponding authors. Fax: +358 142602501, E-mail addresses: and , Tel: +358 408053710 (E.Sievänen).
1. Sample preparation
The experiments are divided into “recrystallization”-, “gelation”- and “cooling” experiments, described in Table S1. In the recrystallization experiments, the sample solution/sol was filtered through cotton near the maximum heating temperature. No filtration was executed in the gelation experiments. In the cooling experiments, additional local cooling was introduced to the sample solution/sol during spontaneous cooling at room temperature, with both unfiltered and filtered samples. Unless explicitly stated, the used amounts of 1 in the samples were 10 mg in 1 mL of solvent for the 1% (m/w) solutions/sols, 20 mg in 1 mL of solvent for the 2% (m/w) solutions/sols, and 10 mg in 2 mL of anisole for ANI-R1. The gelations/precipitations of the cooling experiments were executed in flat-bottomed specimen tubes with nominal dimensions of 50x10x0.6 mm.
As a general note, the solubility of 1 has been experimentally observed to increase with the amount of solvation-precipitation/gelation cycles. At the same time, the nucleation-growth behavior exhibited more predictable behavior and stabilized on consecutive heating and cooling of the sols/solutions. Each sample was exposed to at least ten heating-cooling cycles before conducting the gelation experiment, in order to make sure that the used system was balanced in terms of the nucleation-growth behavior.
S1
Table S1. The prepared solid state samples, experimental classification and methods of analysis. The default concentration is 1% (m/v) unless otherwise noted. The references implicate the studies where the same solvent system has been used previously, with possibly different conditions. The concentration of 1 was 1% in the first study [1], and unknown in the second one [2].
No / Sample / Solvent / Experiment / Analysis1 / BEN-R / Benzene [1] / recrystallization / FTIR, Raman
2 / TOL-R / Toluene (1%) [1] / recrystallization / FTIR, Raman
3 / XYL-R / p-Xylene [1,2] / recrystallization / FTIR, Raman
4 / MES-R / Mesitylene [1] / recrystallization / FTIR, Raman
5 / FLU-R / Fluorobenzene / recrystallization / FTIR, Raman, XRD, PXRD
6 / CHL-R / Chlorobenzene [1,2] / recrystallization / FTIR, Raman
7 / BRO-R / Bromobenzene / recrystallization / FTIR, Raman
8 / IOD-R / Iodobenzene / recrystallization / FTIR, Raman, PXRD
9 / ANI-R1 / Anisole (0.5%) / recrystallization / FTIR, Raman, PXRD
10 / ANI-R2 / Anisole (1%) [1] / recrystallization / FTIR, Raman
11 / ANI-R3 / Anisole (2%) / recrystallization / FTIR, Raman
12 / BEN/CHL-R / Benzene/Chlorobenzene / recrystallization / FTIR, Raman
13 / DCM-R / Dichloromethane [1] / recrystallization / FTIR, Raman
14 / CFR-R / Chloroform [1] / recrystallization / FTIR, Raman
15 / ETH-R / Diethyl ether [2] / recrystallization / FTIR, Raman
16 / TOL-G1 / Toluene (1%) [1] / gelation / FTIR, Raman
17 / TOL-G2 / Toluene (2%) / gelation / FTIR
18 / XYL-G / p-Xylene [1,2] / gelation / FTIR, Raman, PXRD
19 / MES-G / Mesitylene [1] / gelation / FTIR, Raman
20 / CHL-G / Chlorobenzene [1,2] / gelation / FTIR, Raman, PXRD
21 / BRO-G / Bromobenzene / gelation / FTIR, Raman, XRD, PXRD
22 / IOD-G / Iodobenzene / gelation / FTIR, Raman, PXRD
23 / ANI-G1 / Anisole (1%) [1] / gelation / FTIR, Raman
24 / ANI-G2 / Anisole (1%) [1] / gelation / FTIR, Raman
25 / ANI-G3 / Anisole (1%) [1] / gelation/eppendorf / FTIR, Raman
26 / ANI-G4 / Anisole (2%) / gelation / FTIR, Raman, PXRD
27 / ANI-G5 / Anisole (2%) / gelation / FTIR, Raman
28 / BEN/CHL-G / Benzene/Chlorobenzene / gelation / FTIR, Raman
29 / CHL/FLU-G / Chlorobenzene/Fluorobenzene / gelation / FTIR, Raman
30 / ANI/CHL-G / Anisole/Chlorobenzene / gelation / FTIR, Raman
31 / DCM-G / Dichloromethane [1] / gelation / FTIR, Raman, PXRD
32 / CFR-G / Chloroform [1] / gelation / FTIR, Raman
33 / CHL-C / Chlorobenzene [1,2] / shock cooling / FTIR, Raman
34 / IOD-C / Iodobenzene / cooling/filtration / FTIR, Raman
35 / ANI-C1 / Anisole (1%) [1] / cooling / FTIR, Raman
36 / ANI-C2 / Anisole (1%) [1] / cooling/filtration / FTIR, Raman, PXRD
37 / ANI-C3 / Anisole (2%) / cooling / FTIR, Raman
38 / ANI-C4 / Anisole (2%) / cooling/filtration / FTIR, Raman
39 / BEN/CHL-C / Benzene/Chlorobenzene / cooling / FTIR, Raman
40 / ANI/CHL-C / Anisole/Chlorobenzene / cooling / FTIR, Raman
1.1 Recrystallization experiments
General procedure for recrystallized samples (entries 1-15 in Table S1): Gelator 1 was mixed with the solvent and sonicated for three minutes. The homogenized mixture was heated and allowed to cool at room temperature for nine consecutive times. The hot solution/sol was filtered to a recrystallization glass tube through cotton using a pre-heated Pasteur pipette after the tenth heating, and the tube was capped. Sample CFR-R was clear after the last heating, and was not filtered. The gelation status of the samples was checked before the filtration. Samples CHL-R, BRO-R, IOD-R, ANI-R1, ANI-R2, BEN-R, and TOL-R were allowed to crystallize for three days, and samples ANI-R3, XYL-R, MES-R, DCM-R, and BEN/CHL-R for two days, after which the solid was filtered with suction. No precipitation had occurred in CFR-R, and it was allowed to evaporate dry in four days. All of the recrystallization samples were dried in vacuum for six days.
The procedure for FLU-R: Gelator 1 (42 mg) was mixed with approximately 4 mL of fluorobenzene. The suspension was sonicated for five minutes, and warmed with a water bath (50 oC), but the solubility remained poor. The next day the suspension was warmed to a maximum of 65 oC, slightly increasing solubility, and filtered. Short, needle-like crystals started to precipitate within two hours. After three weeks of standing at room temperature in a sealed container, the crystals had grown in size. After six weeks, the crystals were filtered and dried in vacuum for 43 h.
The procedure for ETH-R: Gelator 1 (30.3 mg) was mixed and stirred in 10 mL of boiling diethyl ether. The suspension was filtered through cotton while the temperature was at/near the boiling point. The filtrate was allowed to freely evaporate. Small crystals were observed under optical microscope. After five days, the dry solid was further dried in vacuum for 21-24 h.
1.2 Cooling experiments
General procedure for samples ANI-C1, ANI-C3, and BEN/CHL-C (Table S1): Gelator 1 was sonicated in the solvent for three minutes until the mixture was homogenous. The sols/solutions were heated and allowed to cool in room temperature (samples ANI-C1 and ANI-C3: 10 cycles, and sample BRN/CHL-C: 11 cycles). After the last heating, a copper wire tip cooled in liquid nitrogen was pressed against the flat bottom of the specimen tube. The solid material was allowed to form and stabilize 10-30 min, after which the gelation test was performed. Immediately after, the material was filtered with suction and dried in vacuum for six days.
General procedure for samples IOD-C, ANI-C2, and ANI-C4 (Table S1): The beginning and the end part of the procedure was similar to the preparation of samples ANI-C1, ANI-C3, and BEN/CHL-C. The exception was filtering the samples through cotton to the specimen tubes. The heating and cooling cycles for the samples were as follows (before filtration/after filtration): IOD-C; 9/6, ANI-C2; 10/6, and ANI-C4; 10/9. Samples ANI-C2 and ANI-C4 were dried in vacuum for six days, and sample IOD-C for five days.
1.3 Gelation experiments
General procedure for samples ANI-G1, ANI-G3, ANI-G5, and BEN/CHL-G (Table S1): Gelator 1 was mixed with the solvent and sonicated for three minutes. The homogenized mixture was heated and allowed to cool repeatedly for eight times. After the eighth heating, the hot solution/sol was transferred from the test tube to a specimen tube. The total amount of heating and cooling cycles was ten, except for sample BEN/CHL-G (11 cycles). The gelation status was checked before filtering the formed solid with suction. The samples were dried in vacuum for four days.
The procedure for BRO-G: Gelator 1 (35.7 mg) was mixed with 3 mL of bromobenzene in a test tube, and sonicated the mixture for 30 min with a slight warming (30-50 oC). The next day the material was transferred to a small glass jar, rinsing the original test tube with 570 µL of bromobenzene, which was added among the transferred material. The mixture was heated until the boiling point was reached, and stored in the sealed container. After four months, the solvent was allowed to freely evaporate until the sample was dry. The dried fibrous material was partially homogenized, and vacuum dried for 66 h.
The procedure for CHL-G: Gelator 1 (32.5 mg) was mixed with 3 mL of chlorobenzene in a test tube, sonicated for 30 min with a slight warming (30-50 oC). The next day the material was transferred to a glass jar, rinsing the original tube with 250 µL of chlorobenzene, which was added among the transferred material. The mixture was heated until the boiling point was reached, and stored in the sealed container. The next day the material was determined to be a gel. After three months, the material was filtered and vacuum dried for 43 h.
The procedure for IOD-G: Gelator 1 (40.2 mg) was mixed with 4 mL of iodobenzene, heated until the solid was dissolved as well as possible and stored in the sealed glass vial. After three months, the solvent was allowed to freely evaporate for seven days. The brownish white solid was filtered and vacuum dried for 66 h.
The procedure for DCM-G: Gelator 1 (31.3 mg) was mixed with 3.2 mL of dichloromethane in a test tube. The mixture was sonicated until dispersed and heated for two minutes. The solid was partially soluble at the boiling point of the solvent. After five days in a sealed container, the solid was filtered, dried preliminarily in a stream of nitrogen, and finally dried in vacuum for 47-50 h.
The procedure for ANI-G4: Gelator 1 (35 mg) was mixed with 1.75 mL anisole in a test tube. The mixture was sonicated until homogenous, and heated. The solid was partially soluble at the peak heating temperature. When the suspension cooled, some aggregate settled at bottom, after which a translucent and fibrous gel formed on other parts. After six days, the solid was filtered, and the next day dried in vacuum for 47-50 h.
The procedure for XYL-G: Gelator 1 (38.4 mg) was mixed with 3.84 mL of p-xylene in a test tube. The mixture was sonicated until homogenous, and heated. The solid was partially soluble at the peak heating temperature. The test tube was sealed and stored for five days. The solid was then filtered, and dried in vacuum for 47-50 h.
The procedure for ANI-G2: Gelator 1 (20 mg) was mixed with 2 mL of anisole in a test tube, sonicated for four minutes, and heated for 10-12 min at 110 oC. Most of the solid was dissolved at the peak heating temperature. After three days in a sealed container, a gel with a drop of free solvent had formed. The solvent was then allowed to evaporate freely for one day, after which the material was further allowed to dry on a glass slide. The solid was finally dried in vacuum for 47-50 h, and consisted mostly of the xerogel formed in the test tube.
The procedure for CFR-G: Gelator 1 (5 mg) was mixed with 0.5 mL of chloroform, sonicated for two minutes, and carefully warmed. The solid was partially soluble at the peak heating temperature. The test tube was sealed and stored for five days, after which the solvent was allowed to evaporate. The solid was further dried in vacuum for 47-50 h.
The procedure for TOL-G1: Gelator 1 (5 mg) was mixed with 0.5 mL of toluene in a test tube, sonicated for two minutes, and heated for four minutes at 110 oC. The solid was mostly dissolved at the peak heating temperature. After three days in a sealed container, the solvent was allowed to evaporate for one day. The material was transferred to a glass slide to further evaporate the solvent. Finally, the solid was dried in vacuum for 47-50 h.
The procedure for MES-G: Gelator 1 (5 mg) was mixed with 0.5 mL of mesitylene (1,3,5-trimethylbenzene, 1% w/v), sonicated for 2 min, and heated. The solid was partially soluble at the peak heating temperature. The sample stood sealed at room temperature for three days, after which the solvent was allowed to freely evaporate for one day. The material was put on a glass slide, where the solvent evaporated further. Finally, the solid was dried in vacuum for 47-50 h.
The procedure for TOL-G2: Gelator 1 (15.5 mg) was mixed with 0.775 mL of toluene in a test tube, sonicated for two minutes, and heated for 5-6 minutes at 110 oC. The solid was partially, but quite poorly, soluble at the peak heating temperature. After three days in a sealed container, a gel was formed. The solvent was allowed to evaporate from the gel for one day. The material was put on a glass slide, where the solvent evaporated further. Finally, the solid was dried in vacuum for 47-50 h.
1.4 Other experiments
The procedure for CHL-G: A sol of 1 in chlorobenzene (1% m/v) was heated and cooled for four times. After the fifth heating, the sol was transferred to a plastic eppendorf tube with a preheated Pasteur pipette. The eppendorf tube was placed in liquid nitrogen for 30 seconds, after which the material was filtered with suction when all the solvent had melted. The sample was dried in vacuum for four days.