Salen complexes with dianionic counterions

1. A metal salen complex comprising:

a metal atom selected from cobalt and chromium;

a salen ligand, wherein the salen ligand includes at least one tethered moiety that is either cationic, or capable of being protonated to form a cation; and

a dianionic counterion associated with the metal atom.

2. The metal salen complex of claim 1 , wherein the metal atom is cobalt.

3. The metal salen complex of claim 1 , wherein the complex has a formula:

wherein:

M is the metal atom selected from cobalt or chromium,

R 1a , R 1a′ , R 2a , R 2a′ , R 3a , and R 3a′ are independently a (Z) m group, hydrogen, R, halogen, —OR, —NR 2 , —SR, —CN, —NO 2 , —SO 2 R, —SOR, —SO 2 NR 2 , —CNO, —NRSO 2 R, —NCO, —N 3 , —SiR 3 , —C(O)R, —NRC(O)R, —OC(O)R, —CO 2 R, —OC(O)N(R) 2 , —C(O)NR 2 , —NRC(O)NR—, —NRC(O)OR, or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, phenyl, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated, partially unsaturated or aromatic polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered monocyclic saturated or partially unsaturated heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 12-membered polycyclic saturated or partially unsaturated heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, and an 8- to 10-membered bicyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur;

each R is independently hydrogen or an optionally substituted radical selected from the group consisting of: acyl, carbamoyl, arylalkyl, phenyl, C 1-12 aliphatic, C 1-12 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated, partially unsaturated or aromatic polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered monocyclic saturated or partially unsaturated heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, and an 8- to 10-membered bicyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, sulfur, an oxygen protecting group, or a nitrogen protecting group, or

two R on the same nitrogen atom are taken with the nitrogen to form a 3- to 7-membered heterocyclic ring;

wherein any of [R 2a′ and R 3a′ ], [R 2a and R 3a ], [R 1a and R 2a ], and [R 1a′ and R 2a′ ] may optionally be taken together with the carbon atoms to which they are attached to form one or more rings which may in turn be substituted with (Z) m or one or more R d groups;

R G is selected from the group consisting of:

R J is a bivalent linker selected from the group consisting of: —C(O)—, —C(O)C(O)—, —C(O)—R H —C(O)—, —SO—, —SO 2 —, —P(O)(OR J1 )—, —P(O)R J1 —, —R J1 C═N—, —C(O)—R H —P(O)(OR J1 )—, —C(O)—R H —S(O)—, —C(O)—R H —S(O) 2 —, —SO 2 —R H —P(O)(OR J1 )—, —SO—R H —P(O)(OR J1 )—, and —C(O)R H —;

each R c is optionally present, and if present is, independently at each occurrence, a (Z) m group, halogen, —OR, —NR 2 , —SR, —CN, —NO 2 , —SO 2 R, —SOR, —SO 2 NR 2 , —CNO, —NRSO 2 R, —NCO, —N 3 , —SiR 3 , —C(O)R, —NRC(O)R, —OC(O)R, —CO 2 R, —OC(O)N(R) 2 , —C(O)NR 2 , —NRC(O)NR—, —NRC(O)OR, or an optionally substituted radical selected from the group consisting of arylalkyl, phenyl, C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated, partially unsaturated or aromatic polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered monocyclic saturated or partially unsaturated heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, and an 8- to 10-membered bicyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur,

where two or more R c groups may be taken together with the carbon atoms to which they are attached and any intervening atoms to form one or more optionally substituted rings; and

when two R c groups are attached to the same carbon atom, they may be taken together along with the carbon atom to which they are attached to form a moiety selected from the group consisting of: a 3- to 8-membered spirocyclic ring, a carbonyl, an oxime, a hydrazone, an imine, and an optionally substituted alkene;

each R c′ is, independently at each occurrence, H or R c ;

Y is a bivalent linker selected from the group consisting of: —(CR c′ 2 ) q′ —, —NR—, —N(R)C(O)—, —C(O)NR—, —O—, —C(O)—, —OC(O)—, —C(R) 2 —, —C(O)O—, —S—, —SO—, —SO 2 —, —C(═S)—, —C(═NR)—, or —N═N—, a polyether, C 1-6 aliphatic, a C 3 to C 8 substituted or unsubstituted carbocycle, and a 3- to 8-membered substituted or unsubstituted heterocycle;

each R d is, independently at each occurrence, a (Z) m group, halogen, R, —OR, —NR 2 , —SR, —CN, —NO 2 , —SO 2 R, —SOR, —SO 2 NR 2 , —CNO, —NRSO 2 R, —NCO, —N 3 , —SiR 3 , —C(O)R, —NRC(O)R, —OC(O)R, —CO 2 R, —OC(O)N(R) 2 , —C(O)NR 2 , —NRC(O)NR—, —NRC(O)OR, or an optionally substituted group selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur, 6-10-membered aryl, 5-10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, and 4-7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur;

where two or more R d groups may be taken together with the carbon atoms to which they are attached and any intervening atoms to form one or more optionally substituted rings optionally containing one or more heteroatoms;

R H is selected from the group consisting of R G and —(CR c′ 2 ) q′ ,

R J1 is, independently at each occurrence, selected from the group consisting of:

hydrogen, a metal atom, and an optionally substituted radical selected from the group consisting of acyl carbamoyl, arylalkyl, phenyl, C 1-12 aliphatic, C 1-12 heteroaliphatic, 4- to 7-membered heterocyclyl, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, and an oxygen protecting group;

q′ is an integer from 1 to 6, inclusive;

q is an integer from 0 to 5, inclusive;

x is 0, 1, or 2;

δ represents the net charge of the metal salen complex exclusive of any non-covalently bound counterions and may be any number between −1 and +5; and

(Z) m represents one or more activating moieties attached to the metal salen complex, where

is a linker moiety covalently coupled to the metal salen complex;

each Z is an activating functional group; and

m is an integer from 1 to 4, inclusive, representing the number of Z groups present on the linker moiety.

4. The metal salen complex of claim 3 , wherein at least one of [R 2a and R 3a ] and [R 2a′ and R 3a′ ] are taken together to form an optionally substituted ring.

5. The metal salen complex of claim 4 having the formula:

wherein:

R 4a , R 4a′ , R 5a , R 5a′ , R 6a , R 6a′ , R 7a , and R 7a′ are each independently hydrogen or an R d group; and

wherein [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 optionally substituted rings.

6. The metal salen complex of claim 5 , wherein one or more of R 1a , R 1a′ , R 4a , R 4a′ , R 5a , R 5a′ , R 6a , R 6a′ , R 7a , or R 7a′ are independently a (Z) m group.

7. The metal salen complex of claim 4 , wherein the salen complex is selected from the group consisting of:

wherein:

R 4a , R 4a′ , R 5a , R 5a′ , R 6a , R 6a′ , R 7a , and R 7a′ are each independently hydrogen or an R d group;

wherein [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 optionally substituted rings.

8. The metal salen complex of claim 7 , wherein

is selected from the group:

9. The metal salen complex of claim 7 , wherein

is selected from the group:

10. The metal salen complex of claim 7 , wherein

is oxalate, malonate, maleate, fumurate, succinate, glutarate or phthalate.

11. The metal salen complex of claim 7 , wherein Z is selected from the following:

or a combination of two or more of these, wherein:

each R 1 and R 2 is independently hydrogen or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring;

wherein R 1 and R 2 can be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more additional heteroatoms;

each R 3 is independently hydrogen or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring;

wherein an R 3 group can be taken with an R 1 or R 2 group to form one or more optionally substituted rings; and

each R 4 is independently hydrogen, a hydroxyl protecting group, or an optionally substituted radical selected from the group consisting of C 1-20 acyl, C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring.

12. The metal salen complex of claim 7 , wherein Z is selected from the following:

or a combination of two or more of these,

wherein:

X is an anion;

each R 1 and R 2 is independently hydrogen or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring;

wherein R 1 and R 2 can be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more additional heteroatoms;

each R 3 is independently hydrogen or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl; and an 8- to 14-membered polycyclic aryl ring;

wherein an R 3 group can be taken with an R 1 or R 2 group to form one or more optionally substituted rings;

R 5 is R 2 or hydroxyl;

wherein R 1 and R 5 can be taken together with intervening atoms to form one or more optionally substituted carbocyclic, heterocyclic, aryl, or heteroaryl rings;

each R 6 and R 7 is independently hydrogen or an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring;

wherein R 6 and R 7 can be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more heteroatoms, and an R 6 and R 7 group can be taken with an R 1 or R 2 group to form one or more optionally substituted rings;

each occurrence of R 8 is independently selected from: halogen, —NO 2 , —CN, —NCO, —N 3 , and an optionally substituted radical selected from the group consisting of C 1-20 aliphatic, C 1-20 heteroaliphatic, a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle, a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle, a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, and sulfur, a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur, phenyl, and an 8- to 14-membered polycyclic aryl ring;

where two or more adjacent R 8 groups can be taken together to form an optionally substituted saturated, partially unsaturated, or aromatic 5- to 12-membered ring containing 0 to 4 heteroatoms;

Ring A is an optionally substituted 5- to 10-membered heteroaryl group; and

Ring B is an optionally substituted 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 0-2 heteroatoms in addition to the depicted ring nitrogen atom independently selected from nitrogen, oxygen, and sulfur.

13. The metal salen complex of claim 1 , wherein the complex is selected from:

wherein X − is, independently at each occurrence, an anion or dianion.