Novel Coordination complexes and process of producing polycarbonate by copolymerization of carbon dioxide and epoxide using the same as catalyst

Abstract

Provided are a complex prepared from ammonium salt-containing ligands and having such an equilibrium structural formula that the metal center takes a negative charge of 2 or higher, and a method for preparing polycarbonate via copolymerization of an epoxide compound and carbon dioxide using the complex as a catalyst. When the complex is used as a catalyst for copolymerizing an epoxide compound and carbon dioxide, it shows high activity and high selectivity and provides high-molecular weight polycarbonate, and thus easily applicable to commercial processes. In addition, after forming polycarbonate via carbon dioxide/epoxide copolymerization using the complex as a catalyst, the catalyst may be separately recovered from the copolymer.

1 . A complex represented by Chemical Formula 1:
   [L a MX b ]X c    [Chemical Formula 1]   wherein   M represents a metal element;   L represents a L-type or X-type ligand; p   a represents 1, 2 or 3, wherein when a is 1, L includes at least two protonated groups, and when a is 2 or 3, L(s) are the same or different, and may be linked to each other to be chelated to the metal as a bidentate or tridentate ligand, with the proviso that at least one L includes at least one protonated group and the total number of protonated groups contained in L(s) represent 2 or more;   X(s) independently represent a halide ion; BF 4   − ; ClO 4   − ; NO 3   − ; PF 6   − ; HCO 3   − ; or a (C6-C20)aryloxy anion; (C1-C20)alkylcarboxy anion; (C1-C20)alkoxy anion; (C1-C20)alkylcarbonate anion; (C1-C20)alkylsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkylcarbamate anion; or anion of Meisenheimer salt with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; and   b and c satisfy the condition of “(b+c)=(total number of protonated groups contained in L)+[(oxidation number of metal)−(number of X-type ligands in L)]”, and wherein   the anion of Meisenheimer salt is a compound having the following structural formula:   
       
         
           
           
               
               
           
         
         wherein 
         R represents methyl or H; and 
         R′ is selected from H and nitro (—NO 2 ), with the proviso that at least one of the five R′ radicals represents nitro (—NO 2 ). 
       
     
     
         2 . The complex according to  claim 1 , wherein the protonated group contained in L represents a functional group represented by Chemical Formula 2a, 2b or 2c, and M represents cobalt (III) or chrome (III): 
       
         
           
           
               
               
           
         
         wherein 
         G represents a nitrogen or phosphorus atom; 
         R 1 , R 12 , R 13 , R 21 , R 22 , R 23 , R 24  and R 25  independently represent a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20) aryl or (C6-C20)ar(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; or a hydrocarbyl-substituted metalloid radical of a Group 14 metal, wherein two of R 11 , R 12  and R 13 , or two of R 21 , R 22 , R 23 , R 24  and R 25  may be linked to each other to form a ring; 
         R 31 , R 32  and R 33  independently represent a hydrogen radical; a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20)aryl or (C6-C20)ar(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; or a hydrocarbyl-substituted metalloid radical of a Group 14 metal, wherein two of R 31 , R 32  and R 33  may be linked to each other to form a ring; 
         X′ represents an oxygen atom, sulfur atom or N—R (wherein R represents a hydrogen radical; or a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20)aryl or (C6-C20)ar(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms. 
       
     
     
         3 . The complex according to  claim 2 , wherein L represents a ligand represented by Chemical Formula 3, a represents 2 or 3, and M represents cobalt (III) or chrome (III): 
       
         
           
           
               
               
           
         
         wherein 
         A represents an oxygen or sulfur atom; 
         R 1  through R 5  independently represent a hydrogen radical; a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20)aryl or (C6-C20)aryl(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; or a hydrocarbyl-substituted metalloid radical of a Group 14 metal, wherein the alkyl or alkenyl of R 3  may be further substituted by (C1-C15)alkyl(C6-C20)aryl or (C6-C20)aryl(C1-C15)alkyl, two of R 1  through R 5  may be linked to each other to form a ring, and at least one of R 1  through R 5  includes at least one of Chemical Formulas 2a to 2c; and 
         L(s) are the same or different and may be linked to each other to be chelated to the metal as a bidentate or tridentate ligand. 
       
     
     
         4 . The complex according to  claim 3 , which is a complex represented by Chemical Formula 5: 
       
         
           
           
               
               
           
         
         wherein 
         A 1  and A 2  independently represent an oxygen or sulfur atom; 
         X(s) independently represent a halide ion; BF 4   − ; ClO 4   − ; NO 3   − ; PF 6   − ; HCO 3   − ; or a (C6-C20)aryloxy anion; (C1-C20)alkylcarboxy anion; (C1-C20)alkoxy anion; (C1-C20)alkylcarbonate anion; (C1-C20)alkylsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkylcarbamate anion; or anion of Meisenheimer salt with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; 
         R 41 , R 42 , R 43 , R 44 , R 45  and R 46  are independently selected from hydrogen, tert-butyl, methyl, ethyl, isopropyl and —[YR 51   3-m {(CR 52 R 53 ) n N + R 54 R 55 R 56 } m ], with the proviso that at least one of R 41 , R 42 , R 43 , R 44 , R 45  and R 46  represents —[YR 51   3-m {(CR 52 R 53 ) n N + R 54 R 55 R 56 } m ] (wherein Y represents a carbon or silicon atom, R 51 , R 52 , R 53 , R 54 , R 55  and R 56  independently represent a hydrogen radical; a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20)aryl or (C6-C20)aryl(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; or a hydrocarbyl-substituted metalloid radical of a Group 14 metal, wherein two of R 54 , R 55  and R 56  may be linked to each other to form a ring; m represents an integer from 1 to 3; and n represents an integer from 1 to 20); and 
         b+c−1 represents an integer that equals to the sum of m values of the total —[YR 51   3-m {(CR 52 R 53 ) n N + R 54 R 55 R 56 } m ] radicals contained in the complex represented by Chemical Formula 5. 
       
     
     
         5 . The complex according to  claim 4 , wherein R 41 , R 43 , R 44  and R 45  are independently selected from the group consisting of tert-butyl, methyl, ethyl and isopropyl; R 42  and R 46  independently represent —[CH{(CH 2 ) 3 N + Bu 3 } 2 ] or —[CMe{(CH 2 ) 3 N + Bu 3 } 2 ]; and b+c represents 5. 
     
     
         6 . The complex according to  claim 3 , which is a complex represented by Chemical Formula 6: 
       
         
           
           
               
               
           
         
         Wherein 
         A 1  and A 2  independently represent an oxygen or sulfur atom; 
         X(s) independently represent a halide ion; BF 4   − ; ClO 4   − ; NO 3   − ; PF 6   − ; HCO 3   − ; or a (C6-C20)aryloxy anion; (C1-C20)alkylcarboxy anion; (C1-C20)alkoxy anion; (C1-C20)alkylcarbonate anion; (C1-C20)alkylsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkylcarbamate anion; or anion of Meisenheimer salt with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; 
         R 62  and R 64  are independently selected from tert-butyl, methyl, ethyl, isopropyl and hydrogen, and R 61  and R 63  independently represent —[YR 51   3-m {(CR 52 R 53 ) n N + R 54 R 55 R 56 } m ] (wherein Y represents a carbon or silicon atom, R 51 , R 52 , R 53 , R 54 , R 55  and R 56  independently represent a hydrogen radical; a (C1-C20)alkyl, (C2-C20)alkenyl, (C1-C15)alkyl(C6-C20) aryl or (C6-C20)aryl(C1-C15)alkyl radical with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; or a hydrocarbyl-substituted metalloid radical of a Group 14 metal, wherein two of R 54 , R 55  and R 56  may be linked to each other to form a ring; m represents an integer from 1 to 3; and n represents an integer from 1 to 20); 
         b+c−1 represents an integer that equals to 2×m; and 
         A 3  represents a chemical bond or divalent organic bridge group for linking the two phenyl groups. 
       
     
     
         7 . The complex according to  claim 6 , wherein A 3  represents a chemical bond, (C6-C30)arylene, (C1-C20)alkylene, (C2-C20)alkenylene, (C2-C20)alkynylene, (C3-C20)cycloalkylene or fused (C3-C20)cycloalkylene, or —Si(R 87 )(R 88 —, —CH═N-Q-N═CH—, or the arylene, alkylene, alkenylene, alkynylene, cycloalkylene or fused cycloalkylene may be further substituted by a substituent selected from halogen atoms, (C1-C7)alkyl, (C6-C30)aryl and nitro groups, or may further include at least one hetero atom selected from O, S and N, wherein R 87  and R 88  independently represent (C1-C20)alkyl, (C3-C20)cycloalkyl, (C1-C15)alkyl(C6-C20)aryl, or (C6-C20)aryl(C1-C15)alkyl and Q represents a divalent organic bridge group for linking the two nitrogen atoms. 
     
     
         8 . The complex according to  claim 7 , wherein Q represents (C6-C30)arylene, (C1-C20)alkylene, (C2-C20)alkenylene, (C2-C20)alkynylene, (C3-C20)cycloalkylene or fused (C3-C20)cycloalkylene, wherein the arylene, alkylene, alkenylene, alkynylene, cycloalkylene or fused cycloalkylene may be further substituted by a substituent selected from halogen atoms, (C1-C7)alkyl, (C6-C30)aryl and nitro groups, or may further include at least one hetero atom selected from O, S and N. 
     
     
         9 . The complex according to  claim 8 , wherein R 61  and R 63  independently represent —[CH{(CH 2 ) 3 N + Bu 3 } 2 ] or —[CMe{(CH 2 ) 3 N + Bu 3 } 2 ], Q in the formula of —CH═N-Q-N═CH— represents trans-1,2-cyclohexylene or ethylene, and X independently represents 2,4-dinitrophenolate or BF 4   − . 
     
     
         10 . The complex according to  claim 9 , wherein b+c represents 5, one of the five X radicals represents BF 4 , two of them represent 2,4-dinitrophenolate, and the remaining two X radicals are anions represented by Chemical Formula 10: 
       
         
           
           
               
               
           
         
         wherein 
         R represents methyl or H. 
       
     
     
         11 . The complex according to  claim 8 , which is a complex represented by Chemical Formula 11: 
       
         
           
           
               
               
           
         
         wherein 
         B 1  through B 4  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; 
         R 26  represents primary or secondary (C1-C20)alkyl; 
         R 27  through R 29  are independently selected from (C1-C20)alkyl and (C6-C30)aryl; 
         Q represents a divalent bridge group for linking the two nitrogen atoms; and 
         Z 1  through Z 5  are independently selected from a halide ion; BF 4   − ; ClO 4   − ; NO 3   − ; PF 6   − ; HCO 3   − ; and a (C6-C30)aryloxy anion; (C1-C20)carboxylic acid anion; (C1-C20)alkoxy anion; (C1-C20)alkylcarbonate anion; (C1-C20)alkylsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkylcarbamate anion or anion of Meisenheimer slat with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms, wherein a part of Z 1  through Z 4  coordinated at the cobalt atom may be de-coordinated. 
       
     
     
         12 . The complex according to  claim 11 , wherein B 1  through B 4  independently represent (C2-C6)alkylene; R 26  represents (C1-C7)alkyl; R 27  through R 29  independently represent (C1-C7)alkyl; Q represents ethylene, trans-1,2-cyclohexylene or 1,2-phenylene; Z 1  through Z 5  are independently selected from 2,4-dinitrophenolate and BF 4   − . 
     
     
         13 . The complex according to  claim 12 , wherein B 1  through B 4  independently represent propylene; R 26  and R 27  independently represent methyl; R 28  and R 29  independently represent butyl; Q represents trans-1,2-cyclohexylene; and Z 1  through Z 5  are independently selected from 2,4-dinitrophenolate and BF 4   − . 
     
     
         14 . A method for preparing polycarbonate, comprising carrying out copolymerization of an epoxide compound with carbon dioxide using the complex according to  claim 1  as a catalyst. 
     
     
         15 . The method according to  claim 14 , wherein the epoxide compound is selected from the group consisting of (C2-C20) alkylene oxide substituted or unsubstituted by a halogen or alkoxy; (C4-C20) cycloalkylene oxide substituted or unsubstituted by a halogen or alkoxy; and (C8-C20) styrene oxide substituted or unsubstituted by a halogen, alkoxy, alkyl or aryl. 
     
     
         16 . A method for separately recovering a complex, comprising:
 contacting a solution containing the copolymer and the catalyst and obtained by the method for preparing polycarbonate according to  claim 14  with a solid phase selected from an inorganic material, polymer material or a mixture thereof non-soluble in the solution to form a complex of the solid phase and the catalyst and to separate the copolymer solution;   treating the complex with an acid or a metal salt of a non-reactive anion in a medium that is not capable of dissolving the solid phase to perform an acid-base reaction or salt metathesis; and   carrying out salt metathesis with a salt containing anion X, wherein X independently represents a halide ion; BF 4   − ; ClO 4   − ; NO 3   − ; PF 6   − ; HCO 3   − ; or a (C6-C20)aryloxv anion; (C1-C20)alkvlcarboxv anion; (C1-C20)alkoxv anion; (C1-C20)alkvlcarbonate anion; (C1-C20)alkvlsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkvlcarbamate anion; or anion of Meisenheimer salt with or without at least one of halogen, nitrogen, oxygen, silicon. sulfur and phosphorus atoms and the anion of Meisenheimer salt is a compound having the following structural formula:   
       
         
           
           
               
               
           
         
         wherein 
         R represents methyl or H; and 
         R 1  is selected from H and nitro (−NO 2 ), with the proviso that at least one of the five R 1  radicals represents nitro (—NO 2 ). 
       
     
     
         17 . The method according to  claim 16 , wherein the complex is separately recovered by adding the solution containing the copolymer and the catalyst to a solution containing a solid phase selected from an inorganic material, polymer material and a mixture thereof, followed by filtration; or by passing the solution containing the copolymer and the catalyst through a column packed with the solid phase. 
     
     
         18 . The method according to  claim 17 , wherein the solid inorganic material is surface-modified or non-modified silica or alumina, and the solid polymer material has a functional group reactive to deprotonation by alkoxy anion. 
     
     
         19 . The method according to  claim 18 , wherein the functional group reactive to deprotonation by alkoxy anion is a sulfonic acid group, carboxylic acid group, phenol group or alcohol group. 
     
     
         20 . The method according to  claim 16 ,
 wherein the solution is contacted with silica to form a silica-catalyst complex and to separate the copolymer from the solution;   treating the silica-catalyst complex with an acid or a metal salt of a non-reactive anion in a medium that is not capable of dissolving silica to perform an acid-base reaction or salt metathesis; and   carrying out salt metathesis using a salt containing anion X.   
     
     
         21 . The method according to  claim 14 , wherein the acid is hydrochloric acid or 2,4-dinitrophenol, and the metal salt of a non-reactive anion is DBF 4  or DClO 4  (wherein D represents Li, Na or K). 
     
     
         22 . The method according to  claim 14 , wherein the salt containing anion X is a salt containing Cl anion or 2,4-dinitrophenolate anion. 
     
     
         23 . A method for preparing a complex represented by Chemical Formula 1, comprising:
 reacting L with a metal salt so that L is bound to the metal; and   adding an acid (HX) thereto after L is bound to the metal element and carrying out a reaction in the presence of oxygen to oxidize the metal element and to allow the anion X to be coordinated at the metal element (wherein L and X are the same as defined in Chemical Formula 1):
   [L a MX b ]X c    [Chemical Formula 1] 
   wherein   M represents a metal element;   L represents a L-type or X-type ligand;   a is 1, 2 or 3, wherein when a is 1, L includes at least two protonated groups, and when a is 2 or 3, L(s) are the same or different, and may be linked to each other to be chelated to the metal as a bidentate or tridentate ligand, with the proviso that at least one L includes at least one protonated group and the total number of protonated groups contained in L(s) is 2 or more;   X(s) independently represent a halide ion; BF 4   − ; ClO 4   31  ; NO 3   − ; PF 6   − ; HCO 3   − ; or a (C6-C20)aryloxy anion; (C1-C20)alkylcarboxy anion; (C1-C20)alkoxy anion; (C1-C20)alkylcarbonate anion; (C1-C20)alkylsulfonate anion; (C1-C20)alkylamide anion; (C1-C20)alkylcarbamate anion; or anion of Meisenheimer salt with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus atoms; and   b and c satisfy the condition of “(b+c)=(total number of protonated groups contained in L)+[(oxidation number of metal)−(number of X-type ligands in L)]”, and wherein   the anion of Meisenheimer is a compound having the following structural formula:   
       
         
           
           
               
               
           
         
         wherein 
         R represents methyl or hydrogen; and 
         R 1  is selected from hydrogen and nitro (—NO 2 ), with the proviso that at least one of the five R 1  radicals represents nitro (—NO 2 ). 
       
     
     
         24 . A compound represented by Chemical Formula 17: 
       
         
           
           
               
               
           
         
         wherein 
         B 1  through B 4  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; 
         R 26  represents primary or secondary (C1-C20)alkyl; 
         R 27  through R 29  are independently selected from (C1-C20)alkyl and (C6-C30)aryl; 
         Q is a divalent organic bridge group for linking the two nitrogen atoms with each other; and 
         Z − (s) are independently selected from halide ions, BF 4   − , ClO 4   − , NO 3   − , and PF 6   − . 
       
     
     
         25 . The compound according to  claim 24 , wherein Q represents (C6-C30)arylene, (C1-C20)alkylene, (C2-C20)alkenylene, (C2-C20)alkynylene, (C3-C20)cycloalkylene or fused (C3-C20)cycloalkylene, wherein the arylene, alkylene, alkenylene, alkynylene, cycloalkylene or fused cycloalkylene may be further substituted by a substituent selected from halogen atoms, (C1-C7)alkyl, (C6-C30)aryl and nitro groups, or may further include at least one hetero atom selected from O, S and N. 
     
     
         26 . The compound according to  claim 25 , wherein B 1  through B 4  independently represent propylene; R 26  and R 27  independently represent methyl, and R 28  and R 29  independently represent butyl; Q represents trans-1,2-cyclohexylene; and Z − (s) independently represent iodide anion or BF 4   − . 
     
     
         27 . A method for preparing a compound represented by Chemical Formula 17, comprising:
 adding a diamine compound to a compound represented by Chemical Formula 20 to perform imination and to provide a compound represented by Chemical Formula 21; and   adding a tertiary amine compound thereto to produce a compound represented by Chemical Formula 17:   
       
         
           
           
               
               
           
         
         wherein 
         B 1  through B4, B 9  and B 10  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; 
         R 26  is primary or secondary (C1-C20)alkyl; 
         R 27  through R 29  are independently selected from (C1-C20)alkyl and (C6-C30)aryl; 
         Q is a divalent organic bridge group for linking the two nitrogen atoms with each other; 
         Z − (s) are independently selected from halide ions, BF 4   − , ClO 4   − , NO 3   − , and PF 6   − ; and 
         X 3  and X 4  are independently selected from Cl, Br and I. 
       
     
     
         28 . The method according to  claim 27 , wherein the compound represented by Chemical Formula 20 is obtained by reacting a compound represented by Chemical Formula 15 with a compound represented by Chemical Formula 16 in the presence of an acid catalyst to form a compound represented by Chemical Formula 14, and by attaching an aldehyde group to the compound represented by Chemical Formula 14: 
       
         
           
           
               
               
           
         
         wherein 
         B 9  and B 10  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; R 26  represents primary or secondary (C1-C20)alkyl; R 27  is selected from (C1-C20)alkyl and (C6-C30)aryl; and X 3  and X 4  are independently selected from Cl, Br and I. 
       
     
     
         29 . A phenol derivative represented by Chemical Formula 14: 
       
         
           
           
               
               
           
         
         wherein 
         B 9  and B 10  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; R 26  represents primary or secondary (C1-C20)alkyl; R 27  is selected from (C1-C20)alkyl and (C6-C30)aryl; and X 3  and X 4  are independently selected from Cl, Br and I. 
       
     
     
         30 . A method for preparing a phenol derivative represented by Chemical Formula 14, comprising:
 reacting a phenol compound represented by Chemical Formula 15 with tertiary alcohol compound represented by Chemical Formula 16 in the presence of an acid catalyst:   
       
         
           
           
               
               
           
         
         wherein 
         B 9  and B 10  independently represent (C2-C20)alkylene or (C3-C20)cycloalkylene; R 26  represents primary or secondary (C1-C20)alkyl; R 27  is selected from (C1-C20)alkyl and (C6-C30)aryl; and X 3  and X 4  are independently selected from Cl, Br and I. 
       
     
     
         31 . The method according to  claim 30 , wherein B 9  and B 10  independently represent (C2-C6)alkylene; R 26  represents primary or secondary (C1-C7)alkyl; and R 27  represents (C1-C7)alkyl. 
     
     
         32 . The method according to  claim 31 , wherein B 9  and B 10  independently represent propylene; and R 26  and R 27  independently represent methyl. 
     
     
         33 . The method according to  claim 30 , wherein the acid catalyst is selected from AlCl 3 , inorganic acid and solid acid catalysts.