JP2007238639A - Synthesis of polytrithiocarbonate by alternating copolymerization of episulfide and carbon disulfide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a novel preparation method capable of realizing a high polymerization activity, a highly alternating property and control of molecular weight distribution and regioregularity using, as a raw material, carbon disulfide that can be easily synthesized from carbon and sulfur, and to provide a novel trithiocarbonate alternating copolymer that could not be conventionally prepared. <P>SOLUTION: The polytrithiocarbonate alternating copolymer of formula (1) having a number average molecular weight of 1,000 or larger is prepared by the preparation method of the polytrithiocarbonate alternating copolymer wherein episulfide is polymerized with carbon disulfide in the presence of a nucleophilic reagent and a Lewis acid metal compound. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polytrithiocarbonate obtained by alternating copolymerization reaction of carbon disulfide and episulfide and a method for producing the same.

  In recent years, polymer materials with sulfur atoms introduced into the polymer chain are expected to exhibit characteristic properties such as high colorability, high refractive index, and capture of specific metals. Research on polymer compounds into which sulfur has been introduced has been conducted.

  Japanese Patent Application Laid-Open No. 2005-320532 describes a polyalkylene sulfide having a structure in which oxygen of a polyalkylene oxide is replaced with a sulfur atom as a lens hard coat material. This material has an advantage that it has excellent adhesion to a plastic substrate and has little decrease in refractive index over time.

  In addition, E. Marianucci et al. Measured the refractive index of polythiocarbonates and polydithiocarbonates having a structure in which one or two oxygens contained in the repeating unit of the alternating copolymer polycarbonate were replaced with sulfur. , Reporting the results. According to this paper, the refractive index of polymer materials is increased due to sulfur atoms introduced into the polymer chain (E. Marianucci, et al., Polymer Report, 35 (7), 1994, 1564-1566). .

  For this reason, polytrithiocarbonate having a structure in which all oxygen of polycarbonate is replaced with sulfur is also expected as a novel optical material together with the above compound.

On the other hand, the following research examples have been reported on the synthesis method of polytrithiocarbonate.
Soga et al. Attempted the polymerization reaction of carbon disulfide and ethylene sulfide using diethyl zinc and diethyl cadmium, which are known as anionic coordination polymerization catalysts for episulfide, and confirmed that the yield of the produced polymer was remarkably low. Soga et al. Used a mercury catalyst to improve polymer yield. However, in this method, the alternation of the produced polymer is low, and the structure control of the polymer main chain is difficult (K. Soga, et al., Journal of Polymer Science: Part A: Polymer Chemistry, 14, 677-684 ( 1976)).

  In contrast, Leung et al. Synthesized polytrithiocarbonate by generating trithiocarbonate ions from carbon disulfide and reacting with ethylene dihalide. Even in this method, the yield of the polymer product containing a lower alkylene chain having 2 to 3 carbon atoms is remarkably low. The reason is that the reaction of trithiocarbonate ions with ethylene dihalide preferentially produces a thermodynamically relatively stable 5- or 6-membered cyclic trithiocarbonate, which makes the polymerization reaction difficult to proceed. (LMLeung, et al., Journal of Polymer Science: Part A: Polymer Chemistry, 31, 1799-1806 (1993)).

JP 2005-320532 A E. Marianucci, et al., Polymer Report, 35 (7), 1564-1566 (1994). K. Soga, et al., Journal of Polymer Science: Part A: Polymer Chemistry, 14, 677-684 (1976). L.M.Leung, et al., Journal of Polymer Science: Part A: Polymer Chemistry, 31, 1799-1806 (1993).

As described above, since any of the synthesis methods has a low yield of polytrithiocarbonate polymer, development of a more efficient synthesis method is desired.
On the other hand, since carbon disulfide is a compound that can be easily synthesized from carbon and sulfur, if carbon disulfide can be used as a starting material, it may be an efficient method for introducing sulfur atoms into the polymer chain.

  Therefore, in the present invention, a novel polytrithiocarbonate production method capable of realizing high polymerization activity, high alternation, regioregularity control, etc., using carbon disulfide as a raw material is developed and manufactured conventionally. The object was to provide a novel trithiocarbonate alternating copolymer that could not be obtained.

  As a result of intensive research to achieve the above object, the present inventors have made polytrithiocarbonate alternating copolymers in which the polymer structure is regularly controlled by reacting carbon disulfide with episulfide. A new method for producing the present invention has been found and the present invention has been completed.

  That is, this invention provides the polytrithio carbonate alternate copolymer containing the repeating unit represented by following formula (1).

Wherein R ¹ and R ² are independently a hydrogen atom, halogen atom, cyano, carboxyl, linear or branched C ₁ -C ₂₀ alkyl, C ₂ -C ₂₀ alkenyl or C ₂ -C ₂₀ alkynyl. C ₄ -C ₂₀ cycloalkyl, C ₆ -C ₂₄ aryl or C ₇ -C ₄₀ arylalkyl, or R ¹ and R ² together with the carbon to which they are attached are saturated or unsaturated C ₅ -C ₁₀ alicyclic groups may be formed; the alkyl, alkenyl, alkynyl, cycloalkyl and alicyclic groups and the alkyl portion of the arylalkyl may have one or more double bonds or triple bonds. And the alkyl portion of the alkyl, alkenyl and alkynyl and the arylalkyl may be a halogen atom, hydroxy, Optionally substituted with one or more of the following groups: cycloalkyl, aryl, arylalkyl and alicyclic groups, saturated or unsaturated carbocycles is halogen atom, hydroxy, amino, cyano, nitro, carboxyl, sulfonic acid, linear or _C 1 _{-C 20} branched _alkyl, C 2 _{-C 20} alkenyl or _C 2 _{-C 20 alkynyl,} C 4 -C _It may be substituted with one or more substituents selected from the group consisting of ₂₀ cycloalkyl, or both substituents bonded to two adjacent carbons constituting the carbocycle are combined with the carbon. may form a C ₅ -C ₁₀ cycloaliphatic radical, saturated or unsaturated; wherein said alkyl, alkenyl, alkynyl, cycloalkyl, aryl, The alkyl and alicyclic groups may contain one or more heteroatoms, wherein the heteroatoms are one or more atoms selected from nitrogen, oxygen, sulfur, phosphorus and silicon; Is one or more atoms selected from fluorine, chlorine, bromine and iodine; provided that R ¹ and R ² are not both hydrogen atoms).

One embodiment of the present invention provides an optically active alternating copolymer in which R-configuration and S-configuration asymmetric carbons are regularly arranged in the main chain of the copolymer. That is, in the present invention, when R ¹ is a hydrogen atom in the above formula (1), the asymmetric carbon to which R ² is bonded has only one of R configuration and S configuration. Includes coalescence. Further, the invention relates to a group other than R ^1, R ² are both hydrogen atoms, when R ² is bulky substituent as compared with the R ^1, each R ^1, R ² are attached Optical activity having a regular arrangement in which carbon takes only one of (R configuration, R configuration), (S configuration, S configuration), (R configuration, S configuration) or (S configuration, R configuration). Also included are alternating copolymers.

  Furthermore, the present invention provides a method for producing a polytrithiocarbonate alternating copolymer, wherein the reaction between episulfide and carbon disulfide is carried out in the presence of a nucleophilic reagent.

  One aspect of the present invention is a method for producing a polytrithiocarbonate alternating copolymer, wherein the reaction between episulfide and carbon disulfide is performed in the presence of a nucleophilic reagent and a Lewis acidic metal compound. I will provide a.

  According to another aspect of the present invention, when an episulfide having an asymmetric carbon center on one or both of two carbons constituting the episulfide three-membered ring is used, one of the plurality of episulfide optical isomers is present. Provided is a method for producing an optically active polytrithiocarbonate alternating copolymer characterized by reacting carbon disulfide with a nucleophilic reagent using only one kind as a starting material.

  Furthermore, another aspect of the present invention includes a polytrithiocarbonate alternating copolymer produced by the above method, particularly a polytrithiocarbonate alternating copolymer having optical activity.

  In the present specification, the term “polytrithiocarbonate” means a polymer compound having a structure in which three oxygen contained in a repeating unit of an alternating copolymer of polycarbonate is replaced with sulfur, In particular, it refers to an alternating copolymer containing a repeating unit composed of a carbon chain part having 2 carbon atoms and a trithiocarbonate part, as represented by the above formula (1).

  In the present specification, the term “alkyl” means a substituent represented as a structure in which one hydrogen is removed from a linear or branched hydrocarbon. Preferably carbon number of alkyl is 1-20, More preferably, it is 2-12, More preferably, it is 1-6.

  In this specification, the term “alkenyl” refers to a substituent represented by a structure obtained by removing hydrogen from a terminal double bond carbon in a linear or branched hydrocarbon having an unsaturated double bond at the terminal. means. The carbon number of alkenyl is preferably 2 to 20, more preferably 2 to 12, and still more preferably 2 to 6.

  In the present specification, the term “alkynyl” means a substituent represented by a structure in which a hydrogen is removed from a terminal triple bond carbon in a linear or branched hydrocarbon having an unsaturated triple bond at a terminal. . The number of carbon atoms of the alkynyl is preferably 2-20, more preferably 2-12, and even more preferably 2-6.

  In the present specification, the term “cycloalkyl” means a cyclic alkyl having 3 or more members and includes not only monocyclic but also polycyclic structures. Cyclic alkyl may contain an unsaturated bond, but does not mean an aromatic ring itself. Carbon number of cycloalkyl becomes like this. Preferably it is 4-20, More preferably, it is 5-10.

  In the present specification, the term “aryl” includes at least one aromatic ring, and when a plurality of aromatic rings are present, they may form a condensed ring. Heteroaromatic rings containing atoms may be included. The number of carbon atoms contained in aryl is preferably 6-24, more preferably 6-18. Representative aryl groups include (but are not limited to) phenyl, naphthyl, anthranyl, and the like.

  In the present specification, the term “arylalkyl” means an alkyl group containing at least one aryl as a substituent. Carbon number contained in arylalkyl becomes like this. Preferably it is 7-40, More preferably, it is 7-20, More preferably, it is 7-15.

  In this specification, the term “alicyclic group” is a group having a monocyclic carbocyclic structure, and some bonds may include unsaturated bonds. The number of carbon atoms constituting the ring is preferably 5 to 10, more preferably 5 to 8.

In the present specification, the term “heteroatom” means an element other than carbon, hydrogen, halogen and transition metal, preferably nitrogen, oxygen, sulfur, phosphorus and silicon.
In the copolymer of the present invention, the hetero atom may be included in the substituents R ¹ and R ² by forming a single bond or multiple bond with one or more carbons depending on the valence.

For example, when the hetero atom is oxygen or sulfur, it can be included in the substituent in the following form.
An oxygen atom can be bonded to carbon in an alkyl chain of alkyl or arylalkyl to form an ether bond to form an alkoxy group or an aryloxy group. In addition, oxygen may form a carbonyl (C═O) with a carbon atom of an alkyl chain (including a case where a cyclic or acyclic structure is formed), and the oxygen adjacent to the carbonyl or An ester structure or an amide structure may be given together with nitrogen. When silicon is contained as a hetero atom, it may be present between silicon and carbon to form a silyloxy group. Similarly, the presence of S instead of oxygen can form structures such as thioethers, thionyl (C = S), thioesters, and the like.

Silicon is tetravalent and can be bonded to 1 to 4 carbons, or can be included in a substituent while forming a bond with atoms other than carbon such as fluorine and oxygen.
On the other hand, the halogen atom may be included in the form of replacing any hydrogen atom bonded to the carbon of the alkyl chain or aryl ring that may be included in R ¹ and R ² .

The alternating polytrithiocarbonate of the present invention can be produced by copolymerization of episulfide and carbon disulfide.
Carbon disulfide used in the production method of the present invention is not only a reaction reagent but also a solvent. Therefore, in the method of the present invention, the reaction can be carried out without using an organic solvent other than carbon disulfide.

  The molar ratio of episulfide to carbon disulfide used in the reaction is typically 1: 0.1 to 1:10, but is preferably 1: 0.5 to 1: 3.0, more preferably 1: 1.0 to 1: 2.0.

  The episulfide used in the production method of the present invention is usually a monoepisulfide, preferably an episulfide represented by the following formula (2).

In the above formula (2), R ¹ and R ² independently represent a hydrogen atom, a halogen atom, cyano, carboxyl, linear or branched C ₁ -C ₂₀ alkyl, C ₂ -C ₂₀ alkenyl, or C _2- C ₂₀ alkynyl, C ₄ -C ₂₀ cycloalkyl, C ₆ -C ₂₄ aryl or C ₇ -C ₄₀ arylalkyl, or R ¹ and R ² together with the carbon to which they are attached are saturated or may form a C ₅ -C ₁₀ cycloaliphatic radical of unsaturation; said alkyl, alkenyl, alkynyl, alkyl moiety of cycloalkyl and alicyclic groups, and the arylalkyl is one or more double bonds or In addition, the alkyl, alkenyl and alkynyl and the alkyl part of the arylalkyl may contain a halogen atom, a hydro Optionally substituted with one or more of the following groups: Ci, amino, cyano, nitro, carboxyl, sulfonic acid groups; saturated or unsaturated in the cycloalkyl, aryl, arylalkyl and alicyclic groups carbocycle halogen atom, hydroxy, amino, cyano, nitro, carboxyl, sulfonic acid, _C 1 _{-C 20} alkyl linear or _branched, C 2 _{-C 20} alkenyl or _C 2 _{-C 20} alkynyl, _{C 4} -C ₂₀ optionally substituted with one or more substituents selected from the group consisting of cycloalkyl, or is both substituents attached to two adjacent carbon atoms constituting the carbon ring together with the carbon It may form a C ₅ -C ₁₀ cycloaliphatic radical, saturated or unsaturated Te; said alkyl, alkenyl, alkynyl, cycloalkyl, aryl, a The reelalkyl and alicyclic groups may contain one or more heteroatoms, wherein the heteroatoms are one or more atoms selected from nitrogen, oxygen, sulfur, phosphorus and silicon; Halogen is one or more kinds of atoms selected from fluorine, chlorine, bromine and iodine.

  Specific examples of episulfide compounds include, but are not limited to, ethylene sulfide, propylene sulfide, 1-butene sulfide, 2-butene sulfide, isobutylene sulfide, 1-pentene sulfide, 2-pentene sulfide, and 1-to. Xene sulfide, 1-octene sulfide, 1-dodecene sulfide, cyclopentene sulfide, cyclohexene sulfide, styrene sulfide, vinylcyclohexene sulfide, 3-phenylpropylene sulfide, 3,3,3-trifluoropropylene sulfide, 3-naphthyl Propylene sulfide, 3-phenoxypropylene sulfide, 3-naphthoxypropylene sulfide, butadiene monosulfide, 3-trimethylsilyloxypropylene sulfide, etc. Among them ethylene sulfide, propylene sulfide, cyclohexane Kisensurufido are preferred. These compounds may be used alone or in combination of two or more. When the carbon constituting the three-membered ring of episulfide is an asymmetric center, the optical isomer may be used as a racemic mixture, or only one type of optical isomer may be used alone.

  In the polymerization reaction used in the method for producing a copolymer of the present invention, a thiolate serving as an active terminal is generated by ring opening of an episulfide monomer attacked by a nucleophilic reagent, and carbon disulfide and episulfide are alternately formed. It can be considered to proceed by a mechanism that repeats addition to the active end. Therefore, it is desirable to use a nucleophilic polymerization initiator in the present invention. In the present invention, a conventional anionic nucleophilic reagent considered to be useful for ring opening of epoxides can be used.

  Preferred polymerization initiators include bis (triphenylphosphoranylidene) ammonium salts containing fluoride ion, chloride ion, bromide ion, iodide ion, carboxylate ion, azide ion and alkoxylate ion as counter anions. , Tetraalkylammonium salts, tetraphenylphosphonium salts, ethyltriphenylphosphonium salts, and methyltriphenylphosphonium salts, but are not limited thereto.

  The Lewis acidic metal compound that can be used in the method for producing a copolymer of the present invention functions as a catalyst. Therefore, even if the polymerization reaction occurs even in the absence of the metal compound, the reaction rate and the reaction yield are significantly improved in the presence of the metal compound. It is desirable that the body exists. The Lewis acidic metal compound is preferably a metal complex, and more preferably a metal complex containing a group 3 to group 13 element of the periodic table and an element selected from magnesium and calcium as a central metal. Suitable central metals include rare earth metals such as yttrium and neodymium in addition to aluminum, chromium, manganese, cobalt, nickel, copper, zinc and cadmium. The most preferred central metals are chromium and cobalt. Since any metal can have a plurality of different oxidation states, it is not appropriate to specify the oxidation number. For example, for chromium and cobalt, a compound contained in a trivalent oxidation state can be used.

The metal complex used in the present invention is typically a salt comprising a combination of a cationic metal complex having a planar four-coordinate structure and a counter anion.
The ligand that can constitute the metal complex of the present invention is a single compound or a plurality of neutral compounds or anionic compounds containing either N or O or both as a coordination atom. Preferred ligands include Schiff base ligands having N and O as coordination atoms, polyphyrin ligands having N as coordination atoms, β-diiminate ligands, pyridine ligands, O Acetylacetonato-type, phenoxide-type, benzoate-type ligand, pyridinium alkoxide, chloroacetate, THF, etc. (but not limited to). Moreover, you may select and combine a some ligand from these ligands. Furthermore, a compound containing a plurality of the ligands as a part in the same molecule may be used. For example, in a macrocyclic compound in which aryl groups of phenoxide are linked in a cyclic manner, a plurality of phenoxide moieties can be included in the same ligand.

Examples of Schiff base ligands include salicylaldiminato ligands and salicylideneethylenediiminate (salen) ligands.
The counter anion that can be contained in the metal complex of the present invention is not limited to the following, but is preferably a halide ion such as azide ion, fluoride ion, chloride ion, bromide ion, iodide ion, or acetate ion. Organic acid anions and alkoxylate ions containing carboxylate ions such as benzoate ions.

  Among the above metal and ligand combinations, preferred metal complexes are chromium (III) (Schiff base) chloride and cobalt (III) (Schiff base) represented by the following formulas (3) and (4): ) Chloride.

The polymerization reaction of the present invention is preferably carried out in an inert atmosphere in order to eliminate the influence of oxygen and the like on the reaction intermediate produced.
The reaction is usually carried out at room temperature, but in some cases, it may be carried out in the range from room temperature to the heating reflux temperature of carbon disulfide (46 ° C.).
Although the reaction time may vary depending on the type of catalyst compound used and other reaction conditions, it typically ends in several hours to several tens of hours after the reaction starts.
The by-product cyclic trithiocarbonate is dissolved in a solvent, and when the polymer is obtained as a solid, it can be separated from the by-product by removing the polymer from the solvent. On the other hand, when the polymer is dissolved, only the polymer is precipitated by adding a poor solvent such as methanol, and separated from the by-product.

The polymer can be purified by reprecipitation from a solvent.
The obtained polymer product was identified by measuring ¹ HNMR and ¹³ CNMR spectrum, infrared absorption spectrum, average molecular weight and molecular weight distribution. The regular structure by alternating polymerization was confirmed by the NMR spectrum as described above.

The measurement of the NMR spectrum was performed using JNM-JNM-ECP500 (500 MHz). Moreover, the measurement of the infrared absorption spectrum was performed in the range of 400-4000 cm < ^-1 > by the solution method (carbon disulfide) using SHIMADZU FT-IR8400.

  Tetrahydrofuran was eluted at 40 ° C with a flow rate of 1 ml / min using an MW Science high performance liquid chromatography system (DG660B, PU713, CO631A, UV702, RI704) and two SHODEX KF-804F columns. As a liquid, it measured by converting on the basis of a polystyrene standard.

The specific rotation was measured using DIP-360 manufactured by JASCO Corporation.
In order to investigate the thermal properties of the alternating copolymer of the present invention, the glass transition temperature (Tg) was measured in the temperature range of −50 to 100 ° C. using a DSC30 manufactured by METTLER TOLEDO. In this measurement, since the polymer was decomposed before melting (180 to 200 ° C.), the melting point could not be measured.

The main chain of the alternating copolymer produced by the present invention has a linear structure in which episulfide and carbon disulfide are alternately connected at 1: 1. 1, 2, 4, and 5 show the measurement results of ¹ H and ¹³ C NMR spectra of the polytrithiocarbonate alternating copolymer produced by the method of the present invention. From this spectrum, no hydrogen or carbon signal due to imperfect imperfection is observed in the main chain of the copolymer, and it can be confirmed that the copolymer is a complete alternating copolymer.

The molecular weight of the alternating copolymer of the present invention is not particularly limited, but a typical number average molecular weight M _n measured by gel permeation chromatography (GPC: polystyrene conversion) is 1000 or more, preferably 2,000 to 1,000,000, more preferably 3,000 to 500,000.

The alternating copolymers of the present invention can have a relatively narrow molecular weight distribution (M _w / M _n ). Specifically, it is less than about 4, preferably less than about 2.5, and most preferably about 1.0 to about 1.8.

  In the production method of the present invention, when an optical asymmetric center exists in the raw material episulfide, a polymer corresponding to only one of the optically active enantiomers can be obtained by selecting and using one type of optical isomers. Obtainable.

  For example, when only one of the carbon atoms of the episulfide ring is an asymmetric center, such as propylene sulfide, if one of the two existing optical isomers of episulfide is selected and used, as shown in the figure below, alternating In the main chain of the polymer obtained by the polymerization reaction, carbons of either S or R configuration are inevitably regularly arranged, and the resulting polymer molecule has optical activity.

The same applies to the case where both carbons of the episulfide ring are asymmetric centers. That is, when at least one substituent bonded to two asymmetric carbons is different from the substituent bonded to the other carbon, an alternating copolymer having a controlled steric structure may be obtained. For example, as shown in the figure below, when the substituents R ¹ and R ² are different in bulk, one of the C—S bonds that is easily cleaved by a nucleophilic attack is caused by the steric hindrance of the substituent. The polymerization reaction proceeds with preferential cleavage (in the figure below, the size of the circle represents the bulk of the substituent). Therefore, if only one kind of episulfide optical isomer as shown in the figure below is used as a starting material, a polymer in which asymmetric carbon centers are regularly arranged is produced, and this polymer molecule has optical activity. In this way, it is possible to selectively synthesize only one of the enantiomers.

Effects of the present invention

  By the production method of the present invention, a novel trithiocarbonate alternating copolymer of carbon disulfide and episulfide can be obtained. In particular, in the present invention, an efficient alternating polymerization reaction can be carried out by using a catalyst having a high polymerization activity. In addition, when there are a plurality of optical isomers in the episulfide of the raw material compound, the arrangement of the asymmetric carbon in the main chain of the polymer to be produced can be controlled by selecting a single isomer as the starting material. . Thereby, only one of the symmetrical bodies of the optically active polymer can be selectively synthesized.

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.
The bis (triphenylphosphoranylidene) ammonium chloride used in this example was used as it was without purifying a 97% grade reagent available from Aldrich. As propylene sulfide, a> 98% grade reagent (with stabilizer) available from Tokyo Chemical Industry was dehydrated with calcium hydride and distilled. Carbon disulfide was distilled from a special grade reagent available from Kanto Chemical. The cyclohexene sulfide used was prepared according to the method described in the literature (Organic Synthesis, Collective Volume 4, 232). The optically active propylene sulfide used was prepared according to the method described in the literature (Organometallics 1999, 18, 2061). The chromium (Schiff base) complex as a catalyst was prepared according to the method described in Inorg. Chem. 2004, 43, 6024. The catalyst cobalt (Schiff base) complex used was prepared according to the method described in J. Am. Chem. Soc. 2002, 124, 1307.

Example 1 Synthesis of copolymer by alternating copolymerization reaction of propylene sulfide and carbon disulfide
Synthesis example using 1-A chromium (III) (Schiff base) complex
1-A (3) When the molar ratio of propylene sulfide to carbon disulfide is 1: 1

In a 20 mL Schlenk tube reactor under argon gas atmosphere, chromium complex (13 mg, 0.02 mmol), bis (triphenylphosphoranylidene) ammonium chloride (11.5 mg, 0.02 mmol), propylene sulfide (0.8 mL, 10 mmol) ) And carbon disulfide (0.6 mL) were added, and the mixture was stirred at room temperature for 5 hours. To the reaction vessel, dodecane (0.1 mL, 0.44 mmol) and carbon disulfide (5.0 mL) were added as internal standards. Thereafter, a part of the reaction mixture was extracted, diluted with deuterated chloroform and subjected to ¹ H NMR measurement, and the yield and the copolymer / cyclic body molar ratio were determined. [1] 1 M hydrochloric acid (2 mL) and methanol (5 mL) were gradually added to the remaining reaction mixture, and methanol (100 mL) was further added to precipitate a copolymer. Next, [2] the supernatant was removed by decantation, and carbon disulfide (5 mL) was added to dissolve the copolymer. [1] After the operation of [2] was repeated twice, the polymer was obtained by concentration and vacuum drying [712 mg, 47% yield, M _n = 20,300 (g · mol ⁻¹ ), M _w / M _n = 1.6, T _g = 22.5 ° C]. IR (CHCl ₃ ) 1066, 1045 cm ⁻¹ (C = S). ¹ H NMR (CDCl ₃ ) d 4.52-4.43 (m, 1H), 3.38-3.75 (m, 2H), 1.49 (d, 7.1 Hz, 3H); ¹³ C NMR (CDCl ₃ ): d 221.09, 45.82, 41.62 , 19.11.

1-A (1) When the molar ratio of propylene sulfide to carbon disulfide is 1: 0.5 The amount of carbon disulfide used is adjusted so that the molar ratio of propylene sulfide: carbon disulfide is 1: 0.5. The synthesis was performed in exactly the same procedure as 1-A (3) except that. The results obtained are as shown in the table below.

1-A (2) When the molar ratio of propylene sulfide to carbon disulfide is 1: 0.5 The amount of carbon disulfide used is adjusted so that the molar ratio of propylene sulfide: carbon disulfide is 1: 0.7. The synthesis was performed in exactly the same procedure as 1-A (3) except that. The results obtained are as shown in the table below.

1-A (4) When the molar ratio of propylene sulfide to carbon disulfide is 1: 1.5 The amount of carbon disulfide used is adjusted so that the molar ratio of propylene sulfide: carbon disulfide is 1: 1.5. The above 1-A (3) was synthesized in exactly the same procedure except that. The results obtained are as shown in the table below.

1-A (5) When the molar ratio of propylene sulfide to carbon disulfide is 1: 2.0, the amount of carbon disulfide used is adjusted so that the molar ratio of propylene sulfide: carbon disulfide is 1: 2.0. The synthesis was performed in exactly the same procedure as 1-A (3) except that.

  The results obtained by the above examples are summarized in the following table.

Example of synthesis using 1-B cobalt (III) (Schiff base) complex

Cobalt complex (13 mg, 0.02 mmol), bis (triphenylphosphoranylidene) ammonium chloride (12 mg, 0.02 mmol), propylene sulfide (0.80 mL, 10 mmol) in a 20 mL Schlenk tube reactor under an argon gas atmosphere ) And carbon disulfide (1.2 mL), and the mixture was stirred at room temperature for 5 hours. To the reaction vessel, dodecane (0.10 mL, 0.44 mmol) and carbon disulfide (2.0 mL) were added as internal standards. Thereafter, a part of the reaction mixture was extracted, diluted with deuterated chloroform and subjected to ¹ H NMR measurement, and the copolymer / cyclic body molar ratio was determined. [1] Methanol (100 mL) was added all at once to the remaining reaction mixture to precipitate a copolymer. Next, [2] the supernatant was removed by decantation, and carbon disulfide (5 mL) was added to dissolve the copolymer. [1] After the operation of [2] was repeated twice, the polymer was obtained by concentration and vacuum drying [120 mg, 8% yield, M _n = 10,000 (g · mol ⁻¹ ), M _w / M _n = 2.4].

Synthesis of optically active alternating copolymer using only one kind of 1-C propylene sulfide optical isomer as a starting material

In a 20 mL Schlenk tube reactor under an argon gas atmosphere, chromium complex (16 mg, 0.025 mmol), bis (triphenylphosphoranylidene) ammonium chloride (14 mg, 0.025 mmol), optically active (S) -propylene sulfide ( 0.40 mL, 5 mmol) and carbon disulfide (0.60 mL) were added, and the mixture was stirred at room temperature for 5 hours. To the reaction vessel, dodecane (0.10 mL, 0.44 mmol) and carbon disulfide (2.0 mL) were added as internal standards. Thereafter, a part of the reaction mixture was extracted, diluted with deuterated chloroform and subjected to ¹ H NMR measurement, and the copolymer / cyclic body molar ratio was determined. [1] Methanol (100 mL) was added all at once to the remaining reaction mixture to precipitate a copolymer. Next, [2] the supernatant was removed by decantation, and carbon disulfide (5 mL) was added to dissolve the copolymer. [1] After the operation of [2] was repeated twice, the polymer was obtained by concentration and vacuum drying [595 mg, 79% yield, M _n = 23,200 (g · mol ⁻¹ ), M _w / M _n = 2.2]. Specific rotation: [a] _D ¹⁸ = -213.3 ° (c 0.53, CS ₂ ).

Example 2 Copolymer synthesis by alternating copolymerization of cyclohexene sulfide and carbon disulfide

In a 20 mL Schlenk tube reactor under an argon gas atmosphere, chromium complex (13 mg, 0.02 mmol), bis (triphenylphosphoranylidene) ammonium chloride (12 mg, 0.02 mmol), cyclohexene sulfide (1.1 mL, 10 mmol) ) And carbon disulfide (1.2 mL), and the mixture was stirred at room temperature for 5 hours. To the reaction vessel, dodecane (0.10 mL, 0.44 mmol) and carbon disulfide (2.0 mL) were added as internal standards. Thereafter, a part of the reaction mixture was extracted, diluted with deuterated chloroform and subjected to ¹ H NMR measurement, and the copolymer / cyclic body molar ratio was determined. [1] 1 M hydrochloric acid (2 mL) and methanol (5 mL) were gradually added to the remaining reaction mixture, and then methanol (100 mL) was added all at once to precipitate a copolymer. Next, [2] the supernatant was removed by decantation, and carbon disulfide (5 mL) was added to dissolve the copolymer. [1] The operation of [2] was repeated twice, followed by concentration and vacuum drying to obtain a polymer [550 mg, 29% yield, M _n = 8700 (g · mol ⁻¹ ), M _w / M _n = 1.8]. ¹ H NMR (CDCl ₃ ) d 4.49-4.37 (br, 2H), 2.28-2.16 (br, 2H), 1.82-1.61 (br, 4H), 1.59-1.49 (br, 2H); ¹³ C NMR (CDCl ₃ ) d 219.71 (br), 52.49 (br), 52.26 (br), 31.92 (br), 24.70 (br).

¹ H NMR spectrum of the polythiocarbonate alternating polymer obtained in Example 1 ¹³ C NMR spectrum of the polythiocarbonate alternating polymer obtained in Example 1 IR spectrum of the polythiocarbonate alternating polymer obtained in Example 1 ¹ H NMR spectrum of the polythiocarbonate alternating polymer obtained in Example 2 ¹³ C NMR spectrum of the polythiocarbonate alternating polymer obtained in Example 2

Claims (22)

A polytrithiocarbonate alternating copolymer containing a repeating unit represented by the following formula (1) having a number average molecular weight of 1,000 or more.

Wherein R ¹ and R ² are independently a hydrogen atom, halogen atom, cyano, carboxyl, linear or branched C ₁ -C ₂₀ alkyl, C ₂ -C ₂₀ alkenyl or C ₂ -C ₂₀ alkynyl. C ₄ -C ₂₀ cycloalkyl, C ₆ -C ₂₄ aryl or C ₇ -C ₄₀ arylalkyl, or R ¹ and R ² together with the carbon to which they are attached are saturated or unsaturated C ₅ -C ₁₀ alicyclic groups may be formed; the alkyl, alkenyl, alkynyl, cycloalkyl and alicyclic groups and the alkyl portion of the arylalkyl may have one or more double bonds or triple bonds. And the alkyl portion of the alkyl, alkenyl and alkynyl and the arylalkyl may be a halogen atom, hydroxy, Optionally substituted with one or more of the following groups: cycloalkyl, aryl, arylalkyl and alicyclic groups, saturated or unsaturated carbocycles is halogen atom, hydroxy, amino, cyano, nitro, carboxyl, sulfonic acid, linear or _C 1 _{-C 20} branched _alkyl, C 2 _{-C 20} alkenyl or _C 2 _{-C 20 alkynyl,} C 4 -C _It may be substituted with one or more substituents selected from the group consisting of ₂₀ cycloalkyl, or both substituents bonded to two adjacent carbons constituting the carbocycle are saturated together with the carbon. Or an unsaturated C ₅ -C ₁₀ alicyclic group; the alkyl, alkenyl, alkynyl, cycloalkyl, aryl, aryl The alkyl and alicyclic groups may contain one or more heteroatoms, wherein the heteroatoms are one or more atoms selected from nitrogen, oxygen, sulfur, phosphorus and silicon; Is one or more atoms selected from fluorine, chlorine, bromine and iodine; provided that R ¹ and R ² are not both hydrogen atoms).   The copolymer of Claim 1 whose number average molecular weights are 3,000-500,000. The copolymer according to claim ¹ , wherein R ¹ represents a hydrogen atom, and R ² represents a substituent other than a hydrogen atom. The copolymer according to claim 3, wherein the asymmetric carbon to which R ² is bonded takes only one of R configuration and S configuration. The copolymer according to claim 3 or 4, wherein R ¹ represents a hydrogen atom and R ² represents a methyl group. The copolymer according to claim 1 or 2, wherein R ¹ and R ² both represent a substituent other than a hydrogen atom. Represents R ¹ and R ² are different substituents, R ² is characterized in that it is a bulky group as compared to R ^1, the copolymer of claim 6. The asymmetric carbon to which R ¹ and R ² are bonded has only one of (R configuration, R configuration), (S configuration, S configuration) (R configuration, S configuration) and (S configuration, R configuration). 8. Copolymer according to claim 7, characterized in that The copolymer of claim 6, wherein R ¹ and R ² together with the carbon atom to which they are attached form a cyclohexane ring.   A method for producing a polytrithiocarbonate alternating copolymer by reaction of episulfide and carbon disulfide, wherein the reaction is carried out in the presence of a nucleophilic reagent.   The method according to claim 10, wherein the reaction is carried out in the presence of a Lewis acidic metal compound together with a nucleophilic reagent.   The method according to claim 11, wherein the Lewis acidic metal compound is a metal complex containing a group 3 to group 13 element of the periodic table and an element selected from magnesium and calcium as a central metal.   The method according to claim 12, wherein the metal is at least one metal selected from the group consisting of aluminum, chromium, manganese, cobalt, nickel, copper, zinc, cadmium and rare earth metals.   The method of claim 13, wherein the metal is chromium or cobalt.   The method according to any one of claims 12 to 14, wherein the metal complex is a combination of a cationic complex having a planar four-coordinate structure and a counter anion.   The process according to claim 15, wherein the ligand of the metal complex consists of a single or a plurality of neutral or anionic ligands containing either N or O or both as coordination atoms. .   The method according to claim 16, wherein the ligand is a Schiff base compound. The method according to any one of claims 12 to 17, wherein the cationic complex of the metal complex is represented by the following formula (2) or (3).

  The episulfide has an asymmetric center only in one of two carbons constituting the episulfide three-membered ring, and is composed of only one kind of optical isomers in which a plurality of the episulfides exist. The method according to any one of claims 10 to 18.   The episulfide is different from the substituent in which both of two carbons constituting the episulfide three-membered ring have an asymmetric center and at least one of the substituents bonded to one carbon is bonded to the other carbon, The method according to any one of claims 10 to 18, characterized by comprising only one kind of optical isomers in which a plurality of are present.   A polytrithiocarbonate alternating copolymer produced by the method according to any one of claims 10 to 18.   21. An optically active polytrithiocarbonate alternating copolymer produced by the method of claim 19 or 20.

Images