Polycarbonate polyol compositions and methods

1. A method for the synthesis of aliphatic polycarbonate polyols, the method comprising the steps of:

a) providing a reaction mixture comprising:

(i) one or more epoxides;

(ii) carbon dioxide;

(iii) a metallosalenate metal complex; and

(iv) a chain transfer agent having a structure Y—A—(Y) n , where:

each —Y group is independently a functional group capable of initiating chain growth of epoxide CO 2 copolymers and each Y group may be the same or different;

—A— is a covalent bond or a multivalent moiety; and

n is an integer between 1 and 10, inclusive;

wherein the chain transfer agent and metal complex are present in a molar ratio ranging from 40:1 to 1000:1 or greater than 1000:1;

b) allowing the polymerization reaction to proceed; and

c) terminating the polymerization.

2. The method of claim 1 , wherein each Y group is independently selected from the group consisting of: —OH, —C(O)OH, —C(OR y )OH, —OC(R y )OH, —NHR y , —NHC(O)R y , —NHC═NR y , —NR y C═NH, —NR y C(NR y 2 )═NH; —NHC(NR y 2 )═NR y ; —NHC(O)OR y , —NHC(O)NR y 2 ; —C(O)NHR y , —C(S)NHR y , —OC(O)NHR y , —OC(S)NHR y , —SH, —C(O)SH, —B(OR y )OH, —P(O) a (R y ) b (OR y ) c (OH) d , —OP(O) a (R y ) b (OR y ) c (OH) d , —N(R y )OH, —ON(R y )H, ═NOH, and ═NN(R y )H, where each occurrence of R y is independently —H, or a radical which may be substituted selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, 3- to 12-membered heterocyclic, and 6- to 12-membered aryl, a and b are each independently 0 or 1, c is 0, 1 or 2, d is 0 or 1, and the sum of a, b, and c is 1 or 2.

3. The method of claim 1 , wherein one or more Y groups are hydroxyl or a hydroxyl salt.

4. The method of claim 3 , wherein -A- is a C 3-20 aliphatic chain which may be substituted.

5. The method of claim 3 , wherein -A- is a polyether chain or a polyolefin chain.

6. The method of claim 1 , wherein at least one Y group is a carboxylic acid or a salt thereof.

7. The method of claim 1 , wherein an epoxide has a structure:

where, R 21 , R 22 , R 23 , and R 24 , are each independently selected from the group consisting of: —H, and a group which may be substituted selected from C 1-30 aliphatic, C 6-14 aryl, 3- to 12-membered heterocycle, and 5- to 12-membered heteroaryl, where any two or more of R 21 , R 22 , R 23 , and R 24 can be taken together with intervening atoms to form one or more 3- to 12-membered rings, which may be substituted and contain one or more heteroatoms.

8. The method of claim 1 , wherein an epoxide is selected from the group consisting of:

wherein each R x is, independently, selected from aliphatic which may be substituted, heteroaliphatic which may be substituted, aryl which may be substituted and heteroaryl which may be substituted.

9. The method of claim 1 , wherein an epoxide is ethylene oxide or propylene oxide.

10. The method of claim 1 , wherein the metallosalente metal complex is cobalt salen complex, chromium salen complex, or aluminum salen complex.

11. The method of claim 1 , wherein the metallosalenate metal complex is selected from the group consisting of:

wherein,

M is a metal atom;

Q, at each occurrence is independently O or S;

R 1 and R 1′ are independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, 3- to 14-membered carbocycle which may be substituted, 3- to 14-membered heterocycle which may be substituted, and R 21 ;

R 2 and R 2′ are independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, 3- to 14-membered carbocycle which may be substituted, 3- to 14-membered heterocycle which may be substituted, R 14 , R 20 , and R 21 ;

R 3 and R 3′ are independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, 3- to 14-membered carbocycle which may be substituted, 3- to 14-membered heterocycle which may be substituted, and R 21 ;

represents a moiety which may be substituted covalently linking two nitrogen atoms,

where any of [R 2′ and R 3′ ], [R 2 and R 3 ], [R 1 and R 2 ], and [R 1′ and R 2′ ] may be taken together with intervening atoms to form one or more rings which may in turn be substituted with one or more groups selected from R 14 , R 20 , and R 21 ;

R 14 at each occurrence is independently selected from the group consisting of halogen, C 1 to C 12 aliphatic which may be substituted, 3- to 14-membered carbocycle which may be substituted, 3- to 14-membered heterocycle which may be substituted, —OR 10 , —OC(O)R 13 , —OC(O)OR 13 , —OC(O)NR 11 R 12 , —CN, —CNO, —C(R 13 ) z H (3-z) , —C(O)R 13 , —C(O)OR 13 , —C(O)NR 11 R 12 , —NR 11 R 12 , —NR 11 C(O)R 13 , —NR 11 C(O)OR 13 , —NR 11 SO 2 R 13 , —N + R 11 R 12 R 13 X − , —P + (R 11 ) 3 X − , —P(R 11 ) 3 ═N + ═P(R 11 ) 3 X − , —As + R 11 R 12 R 13 X − , —NCO, —N 3 , —NO 2 , —S(O) x R 13 , and —SO 2 NR 11 R 12 ;

R 20 at each occurrence is independently selected from the group consisting of halogen, —OR 10 , —OC(O)R 13 , —OC(O)OR 13 , —N + (R 11 ) 3 X − , —P + (R 11 ) 3 X − , —P(R 11 ) 3 ═N + ═P(R 11 ) 3 X − , —As + R 11 R 12 R 13 X − , —OC(O)NR 11 R 12 , —CN, —CNO, —C(O)R 13 , —C(O)R 13 , —C(O)NR 11 R 12 , —C(R 13 ) z H (3-z) , —NR 11 R 12 , —NR 11 C(O)R 13 , —NR 11 C(O)OR 13 , —NCO, —NR 11 SO 2 R 13 , —S(O) x R 13 , —S(O) 2 NR 11 R 12 , —NO 2 , —N 3 , and —Si(R 13 ) (3-z) [(CH 2 ) k R 14 ] z ;

R 21 at each occurrence is independently selected from the group consisting of —(CH 2 ) k R 20 and —(CH 2 ) k —Z—(CH 2 ) k R 20 ;

X − is any anion;

Z is a divalent linker selected from the group consisting of —(CH═CH) a —, —(C≡C) a —, —C(O)—, —C(═NOR 11 )—, —C(═NNR 11 R 12 )—, —O—, —OC(O)—, —C(O)O—, —OC(O)O—, —N(R 11 )—, —N(C(O)R 13 )—, —C(O)NR 13 —, —N(C(O)R 13 )O—, —NR 13 C(O)R 13 N—, —S(O) x —, a polyether, and a polyamine;

R 10 at each occurrence is independently selected from the group consisting of —H, C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14-membered heterocycle which may be substituted, —S(O) 2 R 13 , —Si(R 15 ) 3 , —C(O)R 13 , and a hydroxyl protecting group;

R 11 and R 12 at each occurrence are independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14-membered heterocycle which may be substituted, where two or more R 11 or R 12 groups can be taken together with intervening atoms to form a 3- to 10-membered ring which may be substituted;

R 13 at each occurrence is independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, and 3- to 14-membered heterocycle which may be substituted, where two or more R 13 groups on the same molecule may be taken together to form a ring;

R 15 at each occurrence is independently selected from the group consisting of C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, and a 3- to 14-membered heterocycle which may be substituted;

a is 1, 2, 3, or 4;

k is independently at each occurrence an integer from 1 to 8 inclusive;

x is 0, 1, or 2; and

z is 1, 2, or 3.

12. The method of claim 11 , wherein M is selected from the group consisting of Cr, Mn, V, Fe, Co, Mo, W, Ru, Al, and Ni.

13. The method of claim 1 , wherein the metallosalenate metal complex has a formula selected from the group consisting of:

wherein:

M is a metal atom;

L I is a ligand that is a polymerization initiator, and m is an integer between 0 and 2;

R c at each occurrence is independently selected from the group consisting of —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14 membered heterocycle which may be substituted, R 20 , and R 21 ;

R 4a , R 4a′ , R 5 , R 5a′ , R 6a , R 6a′ , R 7a , and R 7′ are each independently hydrogen, a group, halogen, —NO 2 , —CN, —SR 13 , —S(O)R 13 , —S(O) 2 R 13 , —NR 11 C(O)R 13 , —OC(O)R 13 ,

—CO 2 R 13 , —NCO, —N 3 , —OR 10 , —OC(O)NR 11 R 12 , —Si(R 13 ) 3 , —NR 11 R 12 , —NR 11 C(O)R 13 , —NR 11 C(O)OR 13 , or a radical which may be substituted selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, 6- to 10-membered aryl, 5- to 10-membered heteroaryl, and 3- to 7-membered heterocyclic; where [R 1a and R 4a ], [R 1a′ and R 4a′ ] and any two adjacent R 4a , R 4a′ , R 5a , R 5a′ , R 6a , R 6a′ , R 7a , and R 7a′ groups can be taken together with intervening atoms to form one or more rings which may be substituted and contain one or more heteroatoms;

R 1a and R 1a′ are hydrogen when not taken together with R 4a and R 4a′ ;

R′ is R d or a group;

R d is selected from the group consisting of C 1 to C 12 aliphatic which may be substituted, 3- to 14-membered carbocycle which may be substituted, 3- to 14-membered heterocycle which may be substituted, R 20 , and R 21 ;

R 14 at each occurrence is independently halogen, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14-membered heterocycle which may be substituted, —OR 10 , —OC(O)R 13 , —OC(O)OR 13 , —OC(O)NR 11 R 12 , —CN, —CNO, —C(R 13 ) z H (3-z) , —C(O)R 13 , —C(O)OR 13 , —C(O)N 11 R 12 , —NR 11 R 12 , —NR 11 C(O)R 13 , —NR 11 C(O)OR 13 , —NR 11 SO 2 R 13 , —N + R 11 R 12 R 13 X − , —P + (R 11 ) 3 X − , —P(R 11 ) 3 ═N + ═P(R 11 ) 3 X − , —As + R 11 R 12 R 13 X − , —NCO, —N 3 , —NO 2 , —S(O) x R 13 , or —SO 2 NR 11 R 12 ;

R 20 at each occurrence is independently halogen, —OR 10 , —OC(O)R 13 , —OC(O)OR 13 , —N + (R 11 ) 3 X − , —P + (R 11 ) 3 X − , —P(R 11 ) 3 ═N + ═P(R 11 ) 3 X − , —As + R 11 R 12 R 13 X − , —OC(O)NR 11 R 12 , —CN, —CNO, —C(O)R 13 , —C(O)OR 13 , —C(O)N 11 R 12 , —C(R 13 ) z H (3-z) , —NR 11 R 12 , —NR 11 C(O)R 13 , —NR 11 C(O)OR 13 , —NCO, —NR 11 SO 2 R 13 , —S(O) x R 13 , —S(O) 2 NR 11 R 12 , —NO 2 , —N 3 , or —Si(R 13 ) (3-z) [(CH 2 ) k R 14 ] z ;

X − is any anion;

R 21 at each occurrence is independently —(CH 2 ) k R 20 or —(CH 2 ) k —Z—(CH 2 ) k R 20 ;

Z is a divalent linker, wherein the divalent linker is —(CH═CH) a —, —(C≡C) a —, —C(O)—, —C(═NOR 11 )—, —C(═NNR 11 R 12 )—, —O—, —OC(O)—, —C(O)O—, —OC(O)O—, —N(R 11 )—, —N(C(O)R 13 )—, —C(O)NR 13 —, —N(C(O)R 13 )O—, —NR 13 C(O)R 13 N—, —S(O) x —, a polyether, or a polyamine;

R 10 at each occurrence is independently —H, C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14-membered heterocycle which may be substituted, —S(O) 2 R 13 , —Si(R 15 ) 3 , —C(O)R 13 , or a hydroxyl protecting group;

R 11 and R 12 at each occurrence are independently —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted, where two or more R 11 or R 1 groups can be taken together with intervening atoms to form a 3- to 10-membered ring which may be substituted;

R 13 at each occurrence is independently —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted, where two or more R 13 groups on the same molecule may be taken together to form a ring;

R 15 at each occurrence is independently C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted;

a is 1, 2, 3, or 4;

k is independently at each occurrence an integer from 1 to 8 inclusive;

x is 0, 1, or 2;

z is 1, 2, or 3; and

where a group comprises a covalent linker “ ” containing one or more atoms selected from the group consisting of C, O, N, S, and Si; “Z” is an activating functional group having co-catalytic activity in epoxide CO 2 copolymerization, and p is an integer from 1 to 4 indicating the number of individual activating functional groups Z present on a given group.

14. The method of claim 13 , wherein M is selected from the group consisting of Cr, Mn, V, Fe, Co, Mo, W, Ru, Al, and Ni.

15. The method of claim 1 , wherein the metallosalenate metal complex has a formula selected from the group consisting of:

wherein

M is a metal atom;

L I is a ligand that is a polymerization initiator, and m is an integer between 0 and 2;

R 5a , R 5a′ , R 7a , and R 7a′ are each independently hydrogen, a group, halogen, —NO 2 , —CN, —SR 13 , —S(O)R 13 , —S(O) 2 R 13 , —NR 11 C(O)R 13 , —OC(O)R 13 , —CO 2 R 13 , —NCO, —N 3 , —OR 10 , —OC(O)NR 11 R 12 , —Si(R 13 ) 3 , —NR 11 R 12 , —NR 11 C(O)R 13 , or —NR 11 C(O)OR 13 , or an radical which may be substituted wherein said radical which may be substituted is C 1-20 aliphatic, C 1-20 heteroaliphatic, 6- to 10-membered aryl, 5- to 10-membered heteroaryl, or 3- to 7-membered heterocyclic;

R 10 at each occurrence is independently —H, C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, a 3- to 14-membered heterocycle which may be substituted, —S(O) 2 R 13 , —Si(R 15 ) 3 , —C(O)R 13 , or a hydroxyl protecting group;

R 11 and R 12 at each occurrence are independently —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted, where two or more R 11 or R 12 groups can be taken together with intervening atoms to form a 3- to 10-membered ring which may be substituted;

R 13 at each occurrence is independently —H, C 1 to C 12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted, where two or more R 13 groups on the same molecule may be taken together to form a ring; and

R 15 at each occurrence is independently C 1-12 aliphatic which may be substituted, a 3- to 14-membered carbocycle which may be substituted, or a 3- to 14-membered heterocycle which may be substituted; and

where a group comprises a covalent linker “ ” containing one or more of C, O, N, S, or Si; “Z” is an activating functional group having co-catalytic activity in epoxide CO 2 copolymerization; and p is an integer from 1 to 4 indicating the number of individual activating functional groups Z present on a given group.

16. The method of claim 15 , wherein M is selected from the group consisting of Cr, Mn, V, Fe, Co, Mo, W, Ru, Al, and Ni.

17. The method of claim 1 , wherein more than 90% of the linkages formed by the metal complex are carbonate linkages.

18. The method of claim 1 , wherein more than 99% of the linkages formed by the metal complex are carbonate linkages.

19. The method of claim 1 , wherein the polymerization reaction is allowed to proceed until the number average molecular weight of the polymer formed is between 500 and 10,000 g/mol.

20. The method of claim 1 , wherein less than 5% cyclic carbonate is formed as a by-product.