Synthesis and Characterization of Mechanically Linked Graft Polymer

Supplemental Materials

Synthesis and characterization of mechanically linked graft polymer

Daisuke Aoki, Satoshi Uchida, and Toshikazu Takata*

Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama 2-12-1(H-126), Meguro-ku, Tokyo 152-8552, Japan. [email protected]

Table of Contents Materials and Instruments------S2 Synthesis of axle component------S3-S4 Synthesis of wheel component ------S4 Synthesis of 2-PVL_F and 2-PVL_M------S4-S5 Synthesis of the model polymers------S5 References------S6

S1 Materials

Dichloromethane was purchased from ASAHI GLASS CO., LTD., and distilled over CaH2 under a nitrogen atmosphere after being washed with water. δ-valerolactone (98%, Tokyo Kasei Kogyo Co., Ltd. (TCI)), Diphenyl phosphate (99%, TCI), 3,5-dimethylphenyl isocyanate (98%, TCI). Other reagents and solvents commercially available were used without further purification unless otherwise noted. The sec-ammonium axle and dibenzo-24-crown-8 wheel having hydroxyl group were synthesized according to the literatures.

Instruments 1H (400 MHz) and 13C (100 MHz) NMR spectra were recorded on a JEOL AL-400 spectrometer using CDCl3 as the solvent, calibrated using residual undeuterated solvent and tetramethylsilane as the internal standard. IR spectra were recorded on a JASCO FT/IR-230 spectrometer. Melting points were measured on a MELTING POINT APPARATUS SMP3 (Stuart Scientific) instrument. FAB and ESI HR-MS spectra were obtained at the Center for Advanced Material Analysis, Tokyo Institute of Technology on request. MALDI-TOF-MS were taken on a Shimadzu AXIMA-CFR mass spectrometer. The spectrometer was equipped with a nitrogen laser ( = 337 nm) and with pulsed ion extraction. The operation was performed at an accelerating potential of 20 kV by a linear-positive ion mode. The sample polymer solution (1 mg / mL) was prepared in THF. The matrix, dithranol and cationizing agent, sodium trifluoroacetate, was dissolved in THF (10 and 1 mg / mL, respectively). The polymer solution (50 μL) was then mixed with 50  L of the matrix solution. A 1 μL portion of the final solution was deposited onto a sample target plate and allowed to dry in the air at room temperature. Mass values were calibrated by the two-point method with insulin β plus H+ at 3497.96 and R- cyanohydroxy cinnamic acid dimer plus H+ at 379.35. Preparative GPC was carried out using a HPLC LC-918 instrument by Japan Analytical Industry with a Megapak-Gel 201C. Dynamic mechanical analysis (DMA) was measured on IT-DVA200s (ITK, Japan) apparatus.

S2 Scheme S1. Synthesis of axle component.

Methyl 12-aminododecanoate, hydrochloride 12 M hydrochloric acid (8.0 ml, 96.0 mmol) was added to a solution of 12-aminododecanoic acid (11.4 g, 52.9 mmol) in methanol (300 mL), and the reaction mixture was stirred for 8 h at r.t. The mixture was poured into diethyl ether. The precipitates obtained were collected by filtration and dried to give 12.5 g (47.0 mmol, 88.9%) of methyl 12-aminododecanoate, hydrochloride as a colorless crystal.

1 m.p. 141-142 ºC; H-NMR (400 MHz, CDCl3, 298 K): δ (ppm) 1.20–1.44 (m, 14H, alkyl), 1.63

+ – (dd, 2H, J = 6.9, 7.3 Hz, -CH2CH2COO-CH3), 1.76 (dd, 2H, J = 6.9, 7.4 Hz, -CH2CH2NH3 Cl ),

+ – 2.30 (t, 2H, J = 7.3 Hz, -CH2COO-CH3), 2.98 (t, 2H, J = 7.4 Hz, -CH2NH3 Cl ), 3.67 (s, 3H,

13 -OCH3); C-NMR (100 MHz, CDCl3, 298 K): δ (ppm) 25.3, 26.9, 28.0, 29.3, 29.5, 29.6, 29.7,

S3 29.7, 29.8, 34.4, 40.3, 51.7, 174.6. IR (KBr)  2921 (C-H, as), 2849 (C-H, s), 1729 (C=O as) cm–1.

12-(3, 5-dimethylbenzamido) dodecanoic acid methyl ester A solution of 3,5-dimethylbenzoyl chloride (337 mg, 2.00 mmol) in dry THF (5.0 mL) was added dropwise to solution of methyl 12-aminododecanoate hydrochloride (532 mg, 2.00 mmol) and triethyamine (0.56 ml, 4.00 mmol) in dry THF (5.0 mL), then, the mixture was stirred in reflux for 20 h. After cooling to room temperature and evaporation, the residue was dissolved with dichloromethane. The organic layer was washed with water, satd. aq. NaHCO3, and brine, then dried over magnesium sulfate, filtered, and concentrated in vacuo to afford 12-(3,5- dimethylbenzamido) dodecanoic acid methyl ester (601 mg, 1.66 mmol, 83%) as a colorless solid. The mixture was used for next step without further purification.

N-(3,5-dimethylbenzyl)-N-(12-hydroxydodecyl) ammonium hexafluorophosphate (axle) A solution of 12-(3,5-dimethylbenzamido) dodecanoic acid methyl ester (1.20 g, 3.32 mmol) in dry THF (10.0 mL) was added dropwise to a suspension of lithium aluminium hydride (0.25 g, 6.64 mmol) in dry THF (10 mL) at 0 °C. The mixture was refluxed for 18 h. After addition of satd. aq. Na2SO4 at 0 °C, the precipitates formed were filtered off and the filtrate was evaporated in vacuo. The crude was further purified by column chromatography eluting with EtOAc/hexane (3:1) to give a precursor amine. 12 M hydrochloric acid (0.60 mL, 7.20 mmol) was added to a solution of the precursor amine (0.77 g, 2.40 mmol) in the least dissolvable amount of methanol, then the reaction mixture was poured into a large amount of diethyl ether. The precipitates formed were collected by filtration and dried in vacuo. The satd. aq. ammonium hexafluorophosphate was poured into the solution of obtained precipitate in the least amount of methanol until the precipitates were formed. The precipitates formed were collected by filtration, washed with water, and dried in vacuo to give the N-(3,5-dimethylbenzyl)- N-(12- hydroxydodecyl) ammonium hexafluorophosphate 1 (1.05 g, 2.26 mmol, 68%) as a colorless crystal.

1 m.p. 138.9-139.1 ºC; H-NMR (400 MHz, DMSO-d6, 298 K): δ (ppm) 1.18-1.32 (m, 16H,

+ – alkyl), 1.33–1.44 (m, 2H, -CH2CH2OH), 1.49–1.63 (m, 2H, -NH2 PF6 CH2CH2-), 2.29 (s, 6H,

+ – CH3Ar), 2.88 (t, 2H, J = 7.9 Hz, -NH3 PF6 CH2CH2-), 3.37 (br, 3H, -CH2CH2OH), 4.04 (s, 2H,

+ + 13 -ArCH2NH2 ), 4.34 (s, 1H, -CH2CH2OH) 7.07 (br, 3H, Ar), 8.54 (br, 2H, -ArCH2NH2 ). C-

S4 NMR (100 MHz, DMSO-d6, 298 K): δ (ppm) 20.8, 20.9, 25.4, 25.6, 25.9, 28.6, 28.9, 29.0, 29.1, 29.1, 29.2, 32.6, 46.8, 50.2, 60.8, 127.6, 130.4, 131.9, 137.9; IR (KBr)  3254 (vO-H),  2923 (C-H, as),  2851 (C-H, s), 849 (P-F, as), 560 (P-F, s) cm–1.

Synthesis of DB24C8-OH DB24C8-OH was synthesized by using previously reported techniques[1].

Preparation of initiator in solution for ROP. The initiators for ROP having rotaxane structure were synthesized by the complexion of axle components and DB24C8-OH. A typical procedure for the synthesis of initiator 1 is as follows:

Dry CH2Cl2 (6.4 mL) was added to the axle component 2-4 (0.12 g, 0.26 mmol) and W-OH (0.14 g, 0.29 mmol) at r.t. The mixture was sonicated for 30 sec to afford a clear solution of 4-1.

1 H NMR (400 MHz, CDCl3, 298 K): δ (ppm), 0.91–1.61 (m, 20H, alkyl), 2.18 (s, 6H,

+ - + - (CH3)2ArCH2NH2 PF6- ), 3.10 (m, 2H, ArCH2NH2 PF6 -CH2), 3.37–3.73 (m, 8H, DB24C8-γ),

3.75-3.91 (m, 8H, DB24C8-β), 3.91 (brd, 2H, -CH2OH), 4.05–4.29 (m, 8H, DB24C8-α), 4.46–

+ - 4.56 (m, 2H, ArCH2NH2 PF6- ), 4.59 (s, 2H, Ph-CH2-OH), 6.81–7.17 (m, 10H, aromatic).

Synthesis of one-component rotaxane-linked poly(valerolactone) (2-PVL_F and 2-PVL- OH) A typical procedure for the polymerization of δ-VL is as follows: DPP (78.0 mg, 0.31 mmol) was added to a sonicated solution of initiator 1 (the axle component (0.12 g, 0.26 mmol) and

DB24C8-OH (0.14 g, 0.29 mmol) in CH2Cl2 (6.4 mL)). δ-VL (1.32 g, 13.2 mmol) was then added to the solution to initiate the polymerization under a nitrogen atmosphere. After 1.5 h, excess amount of 3,5-dimethylphenyl isocyanate (1.5 mL) was added to the solution and stirred for 12 h to introduce a bulky end-cap group at the termini of the polymer. The polymer was isolated by reprecipitation from CH2Cl2 in ethanol / hexane (1 / 9 : v / v) and purified by preparative gel permeation chromatography with CHCl3 as the eluent to obtain rotaxane-linked graft polymer having PVL as the axle component and graft chain 2-PVL_F (isolated: 1.34 g). In the case of the polymer having no bulky end-cap group at the terminus 2-PVL-OH, the polymer was isolated by reprecipitation from CH2Cl2 in ethanol/hexane (1/9 : v/v) without adding excess amount of 3,5-dimethylphenyl isocyanate.

S5 1 Yield, 80.7%; Mn,NMR, 5,500 g / mol. H-NMR (400 MHz, CDCl3, 298 K): δ (ppm), 0.89–1.47

(m, 20H, alkyl), 1.53–1.80 (m, 2H  n, (-CH2CH2CH2O-)n), 1.55–1.80 (m, 2H  n, (-

+ – COCH2CH2CH2-)n), 2.20 (s, 6H, (CH3)2ArCH2NH2 PF6 ), 2.27 (s, 6H, -CH2OCONHAr(CH3)2),

+ – 2.34 (t, 2H  n, J = 6.4 Hz, (-OCOCH2CH2-)n), 3.17 (brd, 2H, ArCH2NH2 PF6 -CH2), 3.43–3.71

(m, 8H, DB24C8-γ), 3.78–3.91 (m, 8H, DB24C8-β), 4.08 (t, 2H, J = 5.6 Hz, (-CH2CH2O-)n),

4.14–4.28 (m, 8H, DB24C8-α), 4.17 (brd, 2H, -CH2OCONH-), 4.43–4.59 (m, 2H,

+ - ArCH2NH2 PF6- ), 5.08 (s, 2H, Ph-CH2-OCO-), 6.70 (s, 1H, -OCONHAr-), 6.83-7.28 (m, 14H, aromatic).

Acetylation of 2-PVL_F (Synthesis of 2-PVL_M) In a screw-capped test tube 2-PVL_F (120 mg, 0.0210 mmol), acetic anhydride (110 mg, 1.08 mmol), and triethylamine (210 mg, 2.08 mmol) in THF (3.0 mL) was stirred for 24 h at 40 ºC.

The solution was diluted with CH2Cl2 and washed with brine, dried over magnesium sulfate, evaporated in vacuo, and purified by preparative GPC with CHCl3 as the eluent to obtain 2- PVL_M (isolated: 90 mg) as a red solid.

1 Yield, 75.0%; Mn,NMR, 5,000 g / mol. H NMR (400 MHz, CDCl3, 298 K): δ (ppm), 0.88–1.60

COCH2CH2CH2-)n), 2.10-2.25 (m, 12H, (CH3)2ArCH2NAcCH2- and -CH2OCONHAr(CH3)2),

2.30 (s, 3H, ArCH2NAcCH2-), 2.34 (t, 2H  n, J = 6.4 Hz, (-OCOCH2CH2-)n), 3.11–3.39 (m,

2H, ArCH2NAcCH2), 3.46–3.66 (m, 8H, DB24C8-γ), 3.76–3.94 (m, 8H, DB24C8-β), 4.08 (t,

2H, J = 5.6 Hz, (-CH2CH2O-)n), 4.17–4.38 (m, 8H, DB24C8-α), 4.29 (br, 2H, -CH2OCONH-),

4.40 and 4.59 (s, 2H, ArCH2NAc), 5.08 (s, 2H, Ph-CH2-OCO-), 6.70 (s, 1H, -OCONHAr-), 6.71–7.28 (m, 14H, aromatic).

Acetylation of 2-PVL-OH The obtained polymer 2-PVL-OH and triethylamine (1.31 g, 13.0 mmol) in THF (5.0 mL) was stirred for 12h. Excess amount of 3,5-dimethylphenyl isocyanate (1.5 mL) was then added to the solution and stirred for another 12 h to introduce a bulky end-cap group at the terminus of the polymer. The polymer was isolated by reprecipitation from CH 2Cl2 in ethanol/hexane (1/9 : v/v) and purified by preparative gel permeation chromatography

(GPC) with CHCl3 as the eluent to obtain decompositions (isolated: 0.70 g).

S6 1 Yield, 80.2%; Mn,NMR, 5,300 g / mol. H NMR (400 MHz, CDCl3, 298 K): δ (ppm), 1.22–1.36

COCH2CH2CH2-)n), 2.25-2.32 (m, 12H, (CH3)2ArCH2NAcCH2-, -CH2OCONHAr(CH3)2, and

-NCONHAr(CH3)2), 2.34 (t, 2H  n, J = 6.4 Hz, (-OCOCH2CH2-)n), 3.37 (t, 2H, J = 7.8 Hz,

(CH3)2ArCH2N(C=ONAr(CH3)2)CH2CH2-), 3.62–4.00 (m, 16H, DB24C8-γ and DB24C8-β),

4.08 (t, 2H, J = 5.6 Hz, (-CH2CH2O-)n), 4.17–4.38 (m, 8H, DB24C8-α), 4.48 (br, 2H,

-CH2OCONH-), 5.08 (s, 2H, Ph-CH2-OCO-), 6.70–7.28 (m, 19H, aromatic).

Model polymers (both of terminal were balky structure without wheel component)

– DPP (78.0 mg, 0.31 mmol) was added to a stock solution of the axle component A·PF6 (0.12 g,

0.26 mmol) and DB24C8 (0.13 g, 0.29 mmol) in CH2Cl2 (6.4 mL). δ-VL (0.60 mL , 6.50 mmol) was then added to the solution to initiate the polymerization under a nitrogen atmosphere. After

2 h, the polymer was isolated by reprecipitation from CH2Cl2 in ethanol/hexane (1/9 : v/v) and dried. The obtained polymer and triethylamine (1.31 g, 13.0 mmol) in THF (5.0 mL) was stirred to the wheel component should be desliping from the hydroxyl terminus. After 12 h, excess amount of 3,5-dimethylphenyl isocyanate (1.5 mL) was added to the solution and stirred for another 12 h to introduce a bulky end-cap group at the terminus of the polymer. The polymer was isolated by reprecipitation from CH2Cl2 in ethanol/hexane (1/9 : v/v) and purified by preparative gel permeation chromatography (GPC) with CHCl3 as the eluent to obtain model

1 polymer (isolated: 0.70 g). Yield, 77.5%; Mn,NMR, 2,900 g / mol. H NMR (400 MHz, CDCl3,

298 k): δ (ppm), 0.88–1.60 (m, 20H, alkyl), 1.53–1.80 (m, 2H  n, (-CH2CH2CH2O-)n), 1.55–

1.80 (m, 2H  n, (-COCH2CH2CH2-)n), 2.27 (s, 6H, CH3ArCH2NCONPh-), 2.28 (s, 6H,

-CH2OCONHArCH3), 2.28 (s, 6H, CH3ArCH2NCONPhCH3), 2.34 (t, 2H  n, J = 6.4 Hz, (-

OCOCH2CH2-)n), 3.11–3.39 (m, 2H, ArCH2N(CONPhC2H6)CH2), 4.08 (t, 2H, J = 5.6 Hz, (-

CH2CH2O-)n), 4.29 (br, 2H, -CH2OCONH-), 4.40 and 4.59 (s, 2H, ArCH2NAc), 6.70 (s, 1H, -OCONHAr-), 6.71–7.28 (m, 16H, aromatic). The model polymer having polymerization degree of 46 was synthesized as the similar condition as mention above, using 2 equivalent of δ-VL (1.20 mL, 13.0 mmol).

Yield, 80.5%; Mn,NMR, 5,600 g / mol.

References

S7 [1] S. J. Loeb, D. A. Tramontozzi, Org Biomol Chem 2005, 3, 1393-1401.