Bis-phenanthroline iron macrocycle complex for oxygen reduction reaction

Patent metadata

Field	Value
Publication number	US-2020291052-A1
Application number	US-202016820333-A
Country	US
Kind code	A1
Filing date	Mar 16, 2020
Priority date	Mar 14, 2019
Publication date	Sep 17, 2020
Grant date	—

Abstract

Disclosed are compounds, compositions, and methods useful for the oxygen reduction reaction (ORR) and capable of operating efficiently at low overpotentials.

First claim

1 . A compound of Formula I or a salt thereof:

wherein
X 1 and X 2 are independently N, C(R 15 ), (O + )X − , or (S + )X − ;
X − is independently for each occurrence boron tetrafluoride, phosphorus tetrafluoride, phosphorus hexafluoride, alkylsulfonate, fluoroalkylsulfonate, arylsulfonate, bis(alkylsulfonyl)amide, bis(fluoroalkylsulfonyl)amide, bis(arylsulfonyl)amide, (fluoroalkylsulfonyl)(fluoroalkylcarbonyl)amide, halide, nitrate, nitrite, sulfate, hydrogensulfate, alkyl sulfate, aryl sulfate, carbonate, bicarbonate, alkyl carboxylate, aryl carboxylate, phosphate, hydrogen phosphate, dihydrogen phosphate, hypochlorite, or an anionic site of a cation-exchange resin;
R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , and R 14 are independently hydrogen, halogen, —CN, —OR 15 , —CO 2 − (Y + ), —SO 3 H, —SO 3 − (Y + ), —NR 16 R 17 , —NO 2 , substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heterocycloalkyl, haloalkyl, —OC(O)R 20 , —C(O)R 20 , —C(O)OR 20 , —C(O)NR 21 R 22 , —S(O)R 23 , or —SO 2 R 23 ;
Y + is Li + , Na + , K + , Mg 2+ , Ca 2+ , or + NR 16 R 17 R 18 R 19 ;
and
R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , and R 23 are independently hydrogen, haloalkyl, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocycloalkyl.

2 . The compound of claim 1 , wherein X 1 is C(R 15 ) or X 2 is C(R 15 ).

3 . (canceled)

4 . The compound of claim 1 , wherein X 1 is C(R 15 ); and X 2 is C(R 15 ).

5 . The compound of claim 1 , wherein X 1 is N or X 2 is N.

6 . (canceled)

7 . The compound of claim 1 , wherein X 1 is (O + )X − or (S + )X − or X 2 is (O + )X − or (S + )X − .

8 . (canceled)

9 . The compound of claim 1 , wherein R 15 is selected from the group consisting of hydrogen, substituted alkyl, unsubstituted alkyl, substituted cycloalkyl, unsubstituted cycloalkyl, substituted aryl, unsubstituted aryl, substituted heteroaryl, and unsubstituted heteroaryl.

10 - 13 . (canceled)

14 . The compound of claim 1 , wherein:
X 1 is N; and X 2 is N; or X 1 is (O + )X − or (S + )X − ; and X 2 is (O + )X − or (S + )X − .

15 . (canceled)

16 . The compound of claim 1 , wherein at least one, at least two, at least three, or at least four of R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , and R 14 are not hydrogen.

17 - 19 . (canceled)

20 . The compound of claim 1 , wherein R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , and R 14 are hydrogen; and
X 1 is C(R 15 ), (O + )X − , or (S + )X − ; X 1 is C(R 15 ), (O + )X − , or (S + )X − ; and X 2 is C(R 15 ), (O + )X − , or (S + )X − ; X 1 is C(R 15 ); and X 2 is C(R 15 ); X 1 is (O − )X − or (S + )X − ; and X 2 is (O + )X − or (S + )X − ; or X 1 is N; and X 2 is N.

21 - 26 . (canceled)

27 . The compound of claim 1 , wherein:
X 1 is N; and the compound of Formula I is a Bronsted conjugate acid or a quaternary (C 1 -C 6 )alkyl ammonium salt at X 1 ; or X 2 is N; and the compound of Formula I is a Bronsted conjugate acid or a quaternary (C 1 -C 6 )alkyl ammonium salt at X 2 .

28 . (canceled)

29 . The compound of claim 1 , wherein X 1 is N; X 2 is N; the compound of Formula I is a Bronsted conjugate acid or a quaternary (C 1 -C 6 )alkyl ammonium salt at X 1 ; and the compound of Formula I is a Bronsted conjugate acid or a quaternary (C 1 -C 6 )alkyl ammonium salt at X 2 .

30 . A composition, comprising a compound of claim 1 ; and a support material; wherein the compound is in contact with the support material.

31 . The composition of claim 30 , wherein the support material comprises carbon.

32 . (canceled)

33 . The composition of claim 30 , wherein the support material comprises carbon powder, carbon black (CB), multi-walled carbon nanotubes (MWCNT), graphene oxide (GO), or reduced graphene oxide (rGO).

34 . (canceled)

35 . A cathode catalyst, comprising a compound of claim 1 .

36 . A fuel cell, comprising a cathode catalyst of claim 35 .

37 . A method of reducing oxygen, comprising:
in an electrochemical device, applying current to a mixture comprising an aqueous medium, hydrogen gas, oxygen gas, and a compound of claim 1 .

38 . The method of claim 37 , wherein the aqueous medium is an alkaline medium or an acidic medium.

39 . The method of claim 37 , wherein the electrochemical device is an anion-exchange membrane fuel cell or an alkaline metal-air battery.

40 . (canceled)

41 . The method of claim 39 , wherein the electrochemical device is a proton-exchange membrane fuel cell.

Assignees

• Massachusetts Inst Technology

Inventors

• Surendranath Yogesh
• Marshall-Roth Travis

Classifications

• B01J2531/842

  Iron · CPC title

• B01J2531/0241

  Rigid ligands, e.g. extended sp2-carbon frameworks or geminal di- or trisubstitution · CPC title

• B01J2231/62

  Reductions in general of inorganic substrates, e.g. formal hydrogenation, e.g. of N2 · CPC title

• B01J31/183

  with more than one complexing nitrogen atom, e.g. phenanthroline · CPC title

• H01M4/9083

  on carbon or graphite · CPC title