Method and catalyst system for preparing polymers and block copolymers

A method for producing a block copolymer, said block copolymer having a first and second block, using a single catalytic system, wherein the single catalytic system comprises a catalyst of formula (I):

• Wherein:
• [M] is a metal complex having at least one metal atom M coordinated by a ligand system;
• M is Zn, Cr, Co, Mn, Mg, Fe, Ti, Ca, Ge, Al, Mo, W, Ru, Ni or V;
• Z is absent, or is independently selected from -E-, -EX(E)-, or -EX(E)E-;
• X is C or S;
• each E is independently selected from O, S or NRZ, wherein RZ is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl or alkylheteroaryl;
• R is hydrogen, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, silyl or a polymer;
• and when Z is absent, R may additionally be selected from halide, phosphinate, azide and nitro;
• the method comprising the steps of:
• d) providing a mixture comprising:
• i. an epoxide;
• ii. a first monomer or combination of monomers selected from a group (i) to (iii):
• Monomer (i):
• a lactide and/or a lactone,
• Monomer (ii):
• an anhydride, or
• Monomer (iii):
• carbon dioxide, and
• iii. a second monomer or combination of monomers selected from a different group (i) to (iii) to that selected for the first monomer or combination of monomers:
• Monomer (i):
• a lactide and/or a lactone,
• Monomer (ii):
• an anhydride, or
• Monomer (iii):
• carbon dioxide;
• and
• e) contacting the mixture with the single catalytic system;
• wherein the rate of insertion of the first monomer or combination of monomers into the bond between the metal complex [M] and the ligand —Z—R is faster than the rate of insertion of the second monomer or combination of monomers into the bond between the metal complex [M] and the ligand —Z—R;
• wherein when the first monomer or combination of monomers is Group (i), either —Z—R is -E-R, or the mixture comprises a compound [Y], and
• wherein when the second monomer or combination of monomers is Group (i), the mixture comprises a compound [Y].

A method for producing a polyester, comprising contacting a lactone and/or a lactide with a catalyst system having a catalyst of formula (IA):

• wherein
• R1 and R2 are independently hydrogen, halide, a nitro group, a nitrile group, an imine, an amine, an ether group, a silyl ether group, a thioether group, a sulfoxide group, a sulfinate group, or an acetylide group or an optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, aryl, heteroaryl, alicyclic or heteroalicyclic;
• R3 is optionally substituted alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, arylene, heteroarylene or cycloalkylene, wherein alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene and heteroalkynylene may optionally be interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
• R4 is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or alkylaryl;
• R5 is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or alkylaryl;
• E1 is C, E2 is O, S or NH or E1 is N and E2 is O;
• R is hydrogen, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, silyl or a polymer;
• Z is -E-;
• E is —O—, —S—, or NRZ, wherein is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl or alkylheteroaryl;
• each G is independently absent or a neutral or anionic donor ligand which is a Lewis base;
• and
• M is Zn(II), Cr(II), Co(II), Mn(II), Mg(II), Fe(II), Ti(II), Cr(III)-Z—R, Co(III)-Z—R, Mn(III)-Z—R, Fe(III)-Z—R, Ca(II), Ge(II), Al(III)-Z—R, Ti(III)-Z—R, V(III)-Z—R, Ge(IV)-(—Z—R)2 or Ti(IV)+Z—R)2.

A method for producing a polyester, comprising contacting an anhydride and an epoxide with a catalyst system having a catalyst of formula (IA):

• wherein
• R1 and R2 are independently hydrogen, halide, a nitro group, a nitrile group, an imine, an amine, an ether group, a silyl ether group, a thioether group, a sulfoxide group, a sulfinate group, or an acetylide group or an optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, aryl, heteroaryl, alicyclic or heteroalicyclic;
• R3 is optionally substituted alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, arylene, heteroarylene or cycloalkylene, wherein alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene and heteroalkynylene may optionally be interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
• R4 is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or alkylaryl;
• R5 is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or alkylaryl;
• E1 is C, E2 is O, S or NH or E1 is N and E2 is O;
• Z is absent, or is selected from -E-, -EX(E)-, or -EX(E)E-;
• X is C or S;
• E is —O—, —S—, or NRZ, wherein is H, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl or alkylheteroaryl;
• R is hydrogen, or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, or a polymer;
• and when Z is absent, R is additionally selected form halide, phosphinate, azide and nitro;
• each G is independently absent or a neutral or anionic donor ligand which is a Lewis base;
• and
• M is Zn(II), Cr(II), Co(II), Mn(II), Mg(II), Fe(II), Ti(II), Cr(III)-Z—R, Co(III)-Z—R, Mn(III)-Z—R, Fe(III)-Z—R, Ca(II), Ge(II), Al(III)-Z—R, Ti(III)-Z—R, V(III)-Z—R, Ge(IV)-(—Z—R)2 or Ti(IV)-(—Z—R)2.