JP4544842B2 - Method for producing polyrotaxane - Google Patents

Description

  The present invention relates to a method for producing a polyrotaxane, and more particularly, to a method for producing a polyrotaxane from a cyclodextrin substituted with a group whose hydroxyl group does not react with an end cap agent, a linear polymer having hydroxyl groups at both ends, and an end cap agent. .

  Cyclodextrin is known as an excellent host molecule because it can incorporate various organic guests into its hydrophobic inner pore. Among the complex formation between cyclodextrin and organic guest, pseudo-polyrotaxane formation between cyclodextrin and linear polymer is an example of complex formation unique to cyclodextrin. It is also known that polyrotaxane can be synthesized by end-capping the axial end of the formed pseudopolyrotaxane. Here, the polyrotaxane is a polymer having a plurality of rotaxane structures composed of rings and shafts in the molecule, and the pseudopolyrotaxane is a polymer in which the molecular end of the polyrotaxane is not end-capped. However, in the end cap of pseudopolyrotaxane, it is expensive and synthesized as a linear polymer so that the end cap agent selectively reacts with the end of the linear polymer corresponding to the axis of the rotaxane structure rather than the hydroxyl group of cyclodextrin. The polymer which has an amino group at the terminal which is hard to carry out was used (refer nonpatent literature 1). In addition, this reaction system has a problem that the reaction rate is slow.

  On the other hand, permethylcyclodextrin in which the hydroxyl group of cyclodextrin is substituted with a methoxy group is known as a cyclodextrin derivative, and the permethylcyclodextrin is excellent in solubility in organic solvents. Have been widely used in place of unsubstituted cyclodextrins. The permethylcyclodextrin is also excellent as a host molecule like the unsubstituted cyclodextrin, and is known to form a pseudopolyrotaxane by complexing with a linear polymer such as polypropylene glycol or polytetrahydrofuran. (Refer nonpatent literature 2). Here, in the end cap of the pseudopolyrotaxane, since permethylcyclodextrin does not have a hydroxyl group, it is considered possible to use an inexpensive and general polymer having a hydroxyl group at the terminal as a linear polymer.

A. Harada, J. Li, M. Kamachi, Nature, 356, 325 (1992) M. Okada, M. Kamachi, A. Harada, Macromolecules, 32, 7202 (1999)

  However, when the present inventors endcapped a pseudopolyrotaxane formed from permethylcyclodextrin and a polymer having a hydroxyl group at the end in an organic solvent, that is, when a polyrotaxane was synthesized by a liquid phase reaction, The rate of desorption of permethylcyclodextrin from the polymer was much faster than the addition of an end cap to the polyrotaxane, and the polyrotaxane could not be obtained.

  Accordingly, an object of the present invention is to provide a novel method for producing a polyrotaxane by endcapping a pseudopolyrotaxane formed from a substituted cyclodextrin and a polymer having a hydroxyl group at the terminal.

  As a result of diligent studies to achieve the above object, the present inventors have mixed a pseudopolyrotaxane formed from a substituted cyclodextrin and a polymer having a hydroxyl group at the terminal and an end cap agent while applying pressure, thereby producing a pseudopolyrotaxane. It was found that polyrotaxane was produced by solid-phase reaction between the endcap agent and the end cap agent, and the present invention was completed.

  That is, the method for producing a polyrotaxane according to the present invention comprises: (i) generating a pseudopolyrotaxane from a cyclodextrin substituted with a group that does not react with an end-capping agent and a linear polymer with hydroxyl groups at both ends; and (ii) The pseudopolyrotaxane and the end cap agent are reacted in a solid phase.

  In a preferred example of the method for producing a polyrotaxane according to the present invention, the group that does not react with the end cap agent is an alkoxy group. As the alkoxy group, a methoxy group is particularly preferable.

  In another preferred embodiment of the method for producing a polyrotaxane according to the present invention, the polymer is polytetrahydrofuran.

  In another preferred embodiment of the method for producing a polyrotaxane according to the present invention, the end cap agent is an isocyanate or acyl halide having a group bulkier than the inner pore diameter of cyclodextrin. Here, as the isocyanate, 4-tritylphenyl isocyanate and 3,5-dimethylphenyl isocyanate are preferable, and as the acyl halide, 3,5-dimethylbenzoic acid chloride is preferable.

  Moreover, when making the said pseudo poly rotaxane and the said isocyanate react, it is preferable to make a solid phase reaction in presence of n-dibutyltin dilaurate. On the other hand, when the pseudopolyrotaxane and the acyl halide are reacted, they are preferably subjected to a solid phase reaction in the presence of 4-dimethylaminopyridine and triethylamine.

  In another preferred embodiment of the method for producing a polyrotaxane according to the present invention, the pseudopolyrotaxane and the end cap agent are mixed under pressure to cause a solid phase reaction.

  According to the present invention, a polyrotaxane can be produced by applying an end cap to a pseudopolyrotaxane formed from an inexpensive polymer having a hydroxyl group at a terminal and a substituted cyclodextrin. The polyrotaxane is inexpensive and can be produced at low cost because it uses a general polymer having a hydroxyl group at the terminal.

  The present invention is described in detail below. The method for producing a polyrotaxane according to the present invention comprises: (i) generating a pseudopolyrotaxane from a cyclodextrin substituted with a group that does not react with an end-capping agent and a linear polymer having hydroxyl groups at both ends; The polyrotaxane and the end cap agent are subjected to a solid phase reaction. Preferably, the polyrotaxane and the end cap agent are mixed under pressure to cause a solid phase reaction. In the method of the present invention, since the pseudopolyrotaxane and the end cap agent are subjected to a solid phase reaction, the rate at which the substituted cyclodextrin is desorbed from the linear polymer is slow. A polyrotaxane can be produced in a high yield by sufficiently solid-phase reaction with the endcap agent, and the reaction rate between the pseudopolyrotaxane and the endcap agent is sufficiently high.

  In the cyclodextrin in which the hydroxyl group is substituted with a group that does not react with the end cap agent, a group that does not react with the end cap agent (protecting group) can be appropriately selected according to the end cap agent. For example, when isocyanate or acyl halide is used as the end cap agent, examples of the group that does not react with the end cap agent include an alkoxy group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a siloxy group, a sulfonyl group, and a phosphonyl group. Of these, an alkoxy group is preferred. As the alkoxy group, methoxy group, ethoxy group, benzyloxy group, diphenylmethoxy group, trityloxy group, 4-methoxybenzyloxy group, methoxymethoxy group, 1-ethoxyethoxy group, benzyloxymethoxy group, 2-trimethylsilylethoxy group A 2-trimethylsilylethoxymethoxy group, a phenoxy group, a 4-methoxyphenoxy group, and the like can be given. Among these, a methoxy group is particularly preferable.

  The cyclodextrin is also referred to as a cyclic oligosaccharide, in which α-glucopyranose groups are cyclically connected by α-1,4-glycoside bonds, and the number of glucopyranose groups is six α-cyclodextrins (inner Pore diameter: 4.5 mm), β-cyclodextrin having 7 glucopyranose groups (inner pore diameter: 7.0 mm), γ-cyclodextrin having 8 glucopyranose groups (inner pore diameter: 8.5 mm), etc. . After the hydroxyl group of the cyclodextrin is substituted with a group that does not react with the end cap agent, that is, after the hydroxyl group of the cyclodextrin is protected, it is used for complex formation with a polymer described later.

  Examples of the linear polymer having hydroxyl groups at both ends include polypropylene glycol, polytetrahydrofuran, polyethylene glycol, polyoxetane, polytrioxane, poly (1,3-dioxolane), poly (1,3-dioxepane), polysiloxane, and terminal. Examples include hydroxylated polybutadiene and polymerized (oligomerized) products of linear polymers having hydroxyl groups at both ends. Among these, polytetrahydrofuran (PTHF) is used because of its excellent complex formation rate with the substituted cyclodextrin. ) Is preferred. The number average molecular weight (Mn) of the linear polymer is not particularly limited, but is preferably in the range of 1000 to 2000.

  The reaction for generating a pseudopolyrotaxane from a cyclodextrin in which the hydroxyl group is substituted with a group that does not react with an end cap agent and a linear polymer having hydroxyl groups at both ends is described in M. Okada, M. Kamachi, A. Harada, Macromolecules, 32, 7202 (1999). The pseudopolyrotaxane formation reaction is preferably carried out by irradiating ultrasonically in an aqueous solvent at around room temperature. The number of moles of the substituted cyclodextrin per 1 mol of the linear polymer having hydroxyl groups at both ends is not particularly limited by the molecular weight of the polymer, but is preferably in the range of 5 to 12 mol. By adjusting the number of moles of dextrin, the coverage of the polymer with the substituted cyclodextrin can be adjusted. In preparation of the pseudopolyrotaxane, it is preferable to use about twice the required amount of substituted cyclodextrin. Specifically, 10-25 mol of a substituted cyclodextrin is substituted for 1 mol of a linear polymer having hydroxyl groups at both ends. Preference is given to using cyclodextrins.

  As the end cap agent, a compound that selectively reacts with a hydroxyl group of a linear polymer and has a group bulky than the inner pore diameter of cyclodextrin can be used, and examples thereof include isocyanates, acyl halides, and acid anhydrides. can do. By capping the end of the pseudopolyrotaxane (the end of the polymer corresponding to the shaft) with an end-capping agent, the substituted cyclodextrin and the polymer can be linked by a mechanical bond with the rotaxane structure. Here, examples of the bulky group include 3,5-di-t-butylbenzyl group, 3,5-dimethylbenzyl group, 3,5-dinitrobenzyl group, 4-t-butylbenzyl group, trityl group, 4 -Tritylphenyl group, 3,5-dimethylphenyl group and the like.

  Specific examples of the isocyanate include 4-tritylphenyl isocyanate, 3,5-dimethylphenyl isocyanate, 4-ferrocenylphenyl isocyanate, 3,5-di-tert-butylphenyl isocyanate, and the like. Among these, 4-tritylphenyl isocyanate is particularly preferable. Examples of the acyl halide include 3,5-dimethylbenzoic acid chloride, triphenylacetic acid chloride, diphenylacetic acid chloride, 4-tritylbenzoic acid chloride, 3,5-di-tert-butylbenzoic acid chloride, and ferrocenecarbonyl chloride. Etc. Examples of the acid anhydride include acid anhydrides corresponding to the compounds mentioned in the item of acyl halide, specifically 3,5-dimethylbenzoic acid anhydride, triphenylacetic acid anhydride, Examples thereof include diphenylacetic anhydride, 4-tritylbenzoic anhydride, 3,5-di-tert-butylbenzoic anhydride, ferrocenecarboxylic anhydride and the like. The amount of the end cap agent used is preferably in the range of 5 to 30 equivalents (eq) with respect to the hydroxyl group of the linear polymer.

  When isocyanate is used as the end cap agent, the isocyanate and the pseudopolyrotaxane are preferably subjected to an addition reaction in the presence of a catalyst. Examples of the catalyst include n-dibutyltin dilaurate (DBTDL), tetrabutyltin, tributyltin hydride, tributyltin. Chloride, triphenyltin chloride, bis (tributyltin) oxide, tributyltin alkoxide, dibutyltin maleate, dibutyltin oxide, dibutyltin dichloride, imidazole, cyanamide, triethylenediamine, N, N, N ', N'-tetramethylhexamethylenediamine, etc. These catalysts may be used alone or in combination of two or more. Among these catalysts, n-dibutyltin dilaurate is preferable. The amount of the catalyst used is preferably 0.01 to 0.1 mol with respect to 1 mol of the pseudopolyrotaxane.

  When an acyl halide is used as the end cap agent, the acyl halide and the pseudopolyrotaxane are preferably reacted in the presence of a catalyst. Examples of the catalyst include 4-dimethylaminopyridine (DMAP), triethylamine, and triethylenediamine. , Tributylamine, imidazole, pyridine, picoline, lutidine and the like, and 4-dimethylaminopyridine and triethylamine are preferably used in combination. The amount of the catalyst used is preferably 3 to 15 equivalents, more preferably 5 to 10 equivalents, based on the pseudopolyrotaxane.

  In order to cause the pseudopolyrotaxane and the end cap agent to undergo a solid phase reaction, it is preferable to mix the mixture of the pseudopolyrotaxane and the end cap agent while applying pressure, and as the mixing means, mixing while being ground in a mortar. In addition, a ball mill, a kneader, a stone mill, a roller, a screw, a grinder, a mixer, a kneader, or the like can be used. Although it does not specifically limit as a pressure, It is preferable to apply the pressure exceeding atmospheric pressure to the mixture of a pseudo polyrotaxane and an end cap agent. The reaction temperature during the pressurization and mixing is not particularly limited, but it is preferably room temperature or higher. By heating, the yield of polyrotaxane and the coverage of the substituted cyclodextrin with respect to the polymer can be improved. .

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

(Synthesis of permethyl α-cyclodextrin)
29 g of NaH (60% in oil) (NaH; 17 g, 710 mmol) was washed three times with 50 mL of n-hexane, added to 150 mL of dimethylformamide (DMF), and the suspension was mixed with α-cyclodextrin (α- (CD) 12 g (12 mmol) of DMF solution (100 mL) was added dropwise, and the mixture was stirred at room temperature for 30 minutes. Next, the reaction system was brought to 0 ° C. in an ice bath, and 91 mL (1.5 mol) of methyl iodide was added dropwise, followed by stirring at 0 ° C. for 4 hours and further at room temperature for 24 hours. Thereafter, 100 mL of methanol was added to the mixed solution and stirred for several minutes, and the solvent was distilled off under vacuum to concentrate. The concentrated reaction solution was added to 600 mL of ice water, and the target product was extracted from the aqueous phase with 3 × 100 mL of chloroform, washed with 150 mL of saturated aqueous Na ₂ S ₂ O ₄ solution and 2 × 150 mL of saturated brine, and then dried over MgSO ₄ . The solvent was distilled off under reduced pressure. The obtained crude product was dissolved in chloroform and recrystallized with n-hexane to obtain 9.9 g (66%) of white solid permethyl α-cyclodextrin (PMα-CD). The product identification results and reaction scheme are shown below.
mp: 210-213 ° C.
¹ H NMR (270 MHz, CDCl ₃ ): δ = 5.13 (d, J = 3.6 Hz, 6H, C (1) H ), 3.88-3.17 (m, 9019H, C (2-6) H and O (2, 3,6) C H ₃ ) ppm.

(Preparation Example 1 of Pseudopolyrotaxane)
Pseudopolyrotaxane was prepared according to M. Okada, M. Kamachi, A. Harada, Macromolecules, 32, 7202 (1999). To 73 mL of an ion exchange aqueous solution of 15 g (12 mmol) of permethyl α-cyclodextrin (PMα-CD), 730 mg (0.52 mmol) of polytetrahydrofuran (PTHF) having an average molecular weight of 1400 was added, followed by ultrasonic irradiation at 20 ° C. for 30 minutes. The resulting white suspension was allowed to stand overnight at room temperature, then centrifuged and decanted, the gel-like precipitate was washed several times with ion-exchanged water, freeze-dried, and dried with CaCl ₂ . 8.0 g (100% with respect to PTHF) of pseudopolyrotaxane A as a white solid was obtained. The product identification results and reaction scheme are shown below.
¹ H NMR (270 MHz, DMSO-d ₆ ): δ = 5.01 (d, J = 2.2 Hz, 11.0 × 6H, PMα-CD C (1) H ), 3.86-3.03 (m, PMα-CD C ( 2 ~ 6) H and O (2,3,6) C H ₃ , -CH ₂ C H ₂ C H ₂ CH ₂ O-) of PTHF, 1.60 (s, 77H, -C H ₂ CH ₂ CH of PTHF ₂ C H ₂ O-) ppm.
¹³ C NMR (CDCl ₃ ): δ = 99.9, 82.3, 82.0, 81.0, 71.3, 71.1, 70.7, 70.5, 61.7, 58.9, 57.7, 26.6 ppm.

^From the integration ratio of the ¹ H NMR spectrum, the number of PMα-CD per molecule of PTHF was 11.0. Also, from the CPK model, when the length of PMα-CD was 18 mm and the length of the extended chain of PTHF having an average molecular weight of 1400 was 185 mm, it was covered with PMα-CD corresponding to the ring of PTHF corresponding to the shaft. The ratio of the length of the part (hereinafter referred to as the coverage θ) was 107%.

(Synthesis of 4-tritylphenyl isocyanate)
After bubbling HCl gas to 100 mL of a toluene solution of 1.0 g (3.0 mmol) of 4-tritylaniline, 1.3 g (4.5 mmol) of triphosgene was added, and the mixture was heated to reflux for 2 hours. Under vacuum, the solvent and phosgene gas were distilled off under reduced pressure to obtain 1.1 g (100%) of 4-tritylphenyl isocyanate. The product identification results are shown below.
mp: 162-166 ° C.
IR (KBr): 2262, 772, 701cm- ¹ .

(Comparative Example 1)
1.0 mL of a dimethylacetamide (DMAc) solution of 108 mg (0.30 mmol) of ^4- tritylphenyl isocyanate and 0.50 μL (8.5 × 10 ⁻⁴ mmol) of n-dibutyltin dilaurate (DBTDL) was stirred in an Ar atmosphere, and the DMAc solution was mixed with the above solution. Pseudopolyrotaxane A (156 mg, 0.010 mmol) was added, and the mixture was stirred at room temperature for 2 hours. Thereafter, chloroform was added to the reaction solution and the mixture was stirred for several minutes, and the high molecular weight product was separated by HPLC to obtain 22 mg (104%) of a colorless oily product. The product identification results are shown below.
¹ H NMR (270 MHz, DMSO-d ₆ ): δ = 7.27-7.14 (m, 38H, end group Ar H ), 3.34 (s, 77H, —CH ₂ C H ₂ C H ₂ CH ₂ O— of PTHF ), 1.51 (s, 77H, -C H ₂ CH ₂ CH ₂ C H ₂ O-) ppm in PTHF.

Since there was no PMα-CD-derived peak in the ¹ H NMR spectrum of the product, it was confirmed that PMα-CD was detached from PTHF.

Example 1
The pseudopolyrotaxane A 1.57 g (0.10 mmol), 4-tritylphenyl isocyanate 1.09 g (3.0 mmol) and DBTDL 3.0 μL (5.1 × 10 ⁻³ mmol) were pressurized and mixed at room temperature for 90 minutes in a mortar. The mixture was dissolved in chloroform, and the hardly soluble component was separated by filtration and then reprecipitated once in ether and once in methanol to obtain 242 mg (22%) of a white solid product. The product identification results and reaction scheme are shown below.
¹ H NMR (270 MHz, CDCl ₃ , VT60 ° C.): δ = 7.28-7.04 (m, 38H, end group Ar H ), 4.91 (s, 7.2 × 6H, PMα-CD C (1) H ), 3.92 -3.05 (m, C (2-6) H and PM (2-3,6) C H ₃ in PMα-CD, -CH ₂ C H ₂ C H ₂ CH ₂ O- in PTHF, 1.53 (s, 77H, PTHF -C H ₂ CH ₂ CH ₂ C H ₂ O-) ppm.
¹³ C NMR (CDCl ₃ ): δ = 130.7, 127.3, 127.1, 100.2, 82.5, 82.2, 81.3, 71.2, 71.0, 61.7, 58.9, 57.7, 26.7, 26.4 ppm.
IR (KBr): 1736, 1596, 1527 cm ⁻¹ .
GPC (polystyrene standard, eluent: chloroform, UV): Mw / Mn = 1.3, Mn = 10174 (theoretical value 10935).
DSC: Tg = 20.9, Td = 238 ° C.

Peaks derived from PTHF and PMα-CD are present in the ¹ H NMR spectrum of the product, aromatic carbon peaks derived from 4-tritylphenyl isocyanate are observed in the ¹³ C NMR spectrum, and urethane bonds are derived from the IR spectrum. Absorption was observed. Moreover, since Mn measured by GPC almost coincided with the theoretical value, it was confirmed that polyrotaxane was produced. From the integration ratio of ¹ H NMR, n = 7.2 and θ = 70%.

(Examples 2 to 4)
The same procedure as in Example 1 was performed except that the end cap agent, the catalyst, and the reaction time were changed as shown in Table 1. In addition, the usage-amount of an end cap agent is 30 equivalent with respect to pseudo-polyrotaxane A in Example 2 and 4, and 60 equivalent in Example 3. The results are shown in Table 1.

(Examples 5-7)
The same procedure as in Example 2 was performed except that the reaction temperature was changed as shown in Table 2 by heating the mortar on a hot plate. The results are shown in Table 2.

(Example 8)
To 5.0 mL of an ion exchange aqueous solution of 1.0 g (0.82 mmol) of PMα-CD, 50 mg (0.075 mmol) of polytetrahydrofuran (PTHF) having an average molecular weight of 1000 was added, followed by ultrasonic irradiation at 20 ° C. for 30 minutes. The resulting white suspension was allowed to stand at room temperature for 2 days, then centrifuged and filtered. The precipitate was washed several times with ion-exchanged water, dried in vacuo, and then dried with P ₂ O ₅ to give a white 295 mg of solid pseudopolyrotaxane B (75% with respect to PTHF) was obtained. The product identification results are shown below.
¹ H NMR (270 MHz, acetone-d ₆ ): δ = 5.01 (d, J = 3.2 Hz, 5.6 × 6H, PMα-CD C (1) H ), 3.87-3.03 (m, PMα-CD C ( 2-6) H and O (2,3,6) C H ₃ , -CH ₂ C H ₂ C H ₂ CH ₂ O-) of PTHF, 1.59 (s, 55H, -C H ₂ CH ₂ CH of PTHF ₂ C H ₂ O-) ppm.

The pseudopolyrotaxane B 100 mg (0.013 mmol), 4-tritylphenyl isocyanate 140 mg (0.38 mmol) and DBTDL 1.0 μL (1.7 × 10 ⁻³ mmol) were pressurized and mixed at room temperature for 30 minutes in a mortar. The mixture was dissolved in chloroform, and the hardly soluble matter was separated by filtration and then reprecipitated once in ether and once in methanol. The precipitate was purified by HPLC to obtain 36 mg (32%) of a white solid product. The product identification results are shown below.
¹ H NMR (270 MHz, CDCl ₃ , TFA): δ = 7.38-7.06 (m, 38H, end group Ar H ), 5.01 (s, 5.6 × 6H, PMα-CD C (1) H ), 3.99- 3.14 (m, C (2-6) H of PMα-CD and O (2,3,6) C H ₃ , -CH ₂ C H ₂ C H ₂ CH ₂ O-) of PTHF, 1.60 (s, 55H , PTHF -C H ₂ CH ₂ CH ₂ C H ₂ O-) ppm.

Example 9
75 mL (0.038 mmol) of polytetrahydrofuran (PTHF) having an average molecular weight of 2000 was added to 7.5 mL of an ion exchange aqueous solution of 1.5 g (1.2 mmol) of PMα-CD, followed by ultrasonic irradiation at 20 ° C. for 30 minutes. The resulting white suspension was allowed to stand at room temperature for 2 days, then centrifuged and filtered. The precipitate was washed several times with ion-exchanged water, dried in vacuo, and then dried with P ₂ O ₅ to give a white 363 mg of solid pseudopolyrotaxane C (100% with respect to PTHF) was obtained. The product identification results are shown below.
¹ H NMR (270 MHz, acetone-d ₆ ): δ = 5.01 (d, J = 3.2 Hz, 6.1 × 6H, PMα-CD C (1) H ), 3.87-3.03 (m, PMα-CD C ( 2 to 6) H and O (2,3,6) C H ₃ , -CH ₂ C H ₂ C H ₂ CH ₂ O-) of PTHF, 1.60 (s, 110H, -C H ₂ CH ₂ CH of PTHF ₂ C H ₂ O-) ppm.

The pseudo-polyrotaxane C 100 mg (0.011 mmol), 4-tritylphenyl isocyanate 115 mg (0.32 mmol) and DBTDL 1.0 μL (1.7 × 10 ⁻³ mmol) were pressurized and mixed at room temperature for 30 minutes in a mortar. The mixture was dissolved in chloroform, and the hardly soluble component was filtered off and reprecipitated once in ether and once in methanol. The precipitate was purified by HPLC to obtain 43 mg (29%) of a white solid product. The product identification results are shown below.
¹ H NMR (270 MHz, CDCl ₃ , TFA): δ = 7.27-7.19 (m, 38H, end group Ar H ), 5.01 (s, 9.4 × 6H, PMα-CD C (1) H ), 3.86- 3.13 (m, C (2-6) H of PMα-CD and O (2,3,6) C H ₃ , -CH ₂ C H ₂ C H ₂ CH ₂ O-) of PTHF, 1.60 (s, 110H , PTHF -C H ₂ CH ₂ CH ₂ C H ₂ O-) ppm.

The results of Examples 8-9 are summarized in Table 3.

  In Example 9, it is considered that the reason why n and θ increased after the end cap was added was that the pseudopolyrotaxane C was not a uniform pseudopolyrotaxane.

  The polyrotaxane obtained by the method of the present invention can be used for new materials and functional materials. The polyrotaxane can be applied to molecular switches and the like.

Claims (10)

  (i) generating a pseudopolyrotaxane from a cyclodextrin substituted with a group in which the hydroxyl group does not react with the endcap agent and a linear polymer having hydroxyl groups at both ends, and (ii) combining the pseudopolyrotaxane and the endcap agent in a solid phase. A process for producing a polyrotaxane, characterized by reacting.   The method for producing a polyrotaxane according to claim 1, wherein the group that does not react with the end cap agent is an alkoxy group.   The method for producing a polyrotaxane according to claim 2, wherein the alkoxy group is a methoxy group.   The method for producing a polyrotaxane according to claim 1, wherein the polymer is polytetrahydrofuran.   The method for producing a polyrotaxane according to claim 1, wherein the end cap agent is an isocyanate or acyl halide having a group bulkier than the inner pore diameter of cyclodextrin.   The method for producing a polyrotaxane according to claim 5, wherein the isocyanate is selected from the group consisting of 4-tritylphenyl isocyanate and 3,5-dimethylphenyl isocyanate.   6. The method for producing a polyrotaxane according to claim 5, wherein the acyl halide is 3,5-dimethylbenzoic acid chloride.   The method for producing a polyrotaxane according to claim 5, wherein the reaction between the pseudopolyrotaxane and the isocyanate is carried out in the presence of n-dibutyltin dilaurate.   The method for producing a polyrotaxane according to claim 5, wherein the reaction between the pseudopolyrotaxane and the acyl halide is carried out in the presence of 4-dimethylaminopyridine and triethylamine.   The method for producing a polyrotaxane according to claim 1, wherein the pseudo-polyrotaxane and the end cap agent are mixed under pressure to cause a solid phase reaction.