Derivatization and solubilization of insoluble classes of fullerenes

• US 7,671,230 B2
• Filed: 10/01/2002
• Issued: 03/02/2010
• Est. Priority Date: 10/01/2001
• Status: Expired due to Fees

• Current Assignee: Tda Research, Inc.
• Original Assignee: Tda Research, Inc.
• Inventors: Bolskar, Robert D., Alford, J. Michael
• Primary Examiner(s): OH, TAYLOR V
• Application Number:
  US10/263,375
• Publication Number:
  US 20030065206A1
• Time in Patent Office: 2,709 Days
• Field of Search: 558/87, 558/357, 560/8, 560/82, 564/161, 977/734, 977/735, 977/737
• US Class Current: 560/82
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C07C 2604/00 Fullerenes, e.g. C60 buckminsterfullerene or C70
• CPC Class Codes: C07C 49/792 containing rings other than six-membered aromatic rings
• CPC Class Codes: C07C 69/753 of polycyclic acids
• CPC Class Codes: C07F 9/3839 Polyphosphonic acids
• CPC Class Codes: Y10S 977/734 Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
• CPC Class Codes: Y10S 977/735 Carbon buckyball
• CPC Class Codes: Y10S 977/737 having a modified surface

Abstract

This invention provides improved methods for the derivatization and solubilization of fullerenes, which are particularly useful for those fullerenes that are normally insoluble and which are specifically applied, among others, to endohedral fullerenes, including endohedral metallofullerenes; empty fullerenes, including small-bandgap fullerenes and other insoluble fullerenes and to very high molecular weight fullerenic materials generated in fullerenic soot, including giant fullerenes, fullerenic polymers, carbon nanotubes and metal-carbon nanoencapsulates. More specifically the invention relates to improved methods for cyclopropanation of fullerenes. Specific reaction conditions are provided which allow for cyclopropanation reactions to be successfully performed for the first time on insoluble classes of fullerenes. Also provided is a method for purification of one or more fullerenes from a fullerenic material containing the one or more fullerenes in addition to non-fullerenic carbonaceous material, particularly amorphous carbonaceous material, by derivatizing one or more fullerenes using the methods of the invention and separating soluble derivatizes fullerenes from insoluble materials.

Claims

1. A method for derivatizing one or more fullerenes comprising the steps of:

a. providing the one or more fullerenes as a solid; and

b. contacting the fullerene solid with a suitable base, and a cyclopropanation reagent in the presence of an at least moderately polar aprotic solvent in which the one or more fullerenes to be derivatized are insoluble or substantially insoluble,

wherein the cyclopropanation reagent has the formula;

2. The method of claim 1 wherein n is 6-10.

3. The method of claim 1 wherein x is 1-5.

4. The method of claim 1 wherein LG is —

Cl, —

Br, or —

I.

5. A method for derivatizing fullerenes comprising the steps of:

providing one or more fullerenes as a solid; and

contacting the fullerene solid with a solution comprising an at least moderately polar aprotic solvent in which the one or more fullerenes are soluble at a level of about 0.001 mg/mL or less, a suitable base, and a cyclopropanation reagent, wherein the one or more fullerenes is an empty small bandgap fullerene.

35. The method of claim 5 wherein the solvent is tetrahydrofuran, 1,4-dioxane or dimethoxyethane.

6. A method for derivatizing fullerenes comprising the steps of:

providing one or more fullerenes as a solid; and

contacting the fullerene solid with a solution comprising an at least moderately polar aprotic solvent in which the one or more fullerenes are soluble at a level of about 0.001 mg/mL or less, a suitable base, and a cyclopropanation reagent

wherein the fullerene is an endohedral M@C60 class fullerene and M is an element selected from the group consisting of lanthanide metals, actinide metals, transition metals, alkali metals, and alkaline earth metals.

7. The method of claim 6 wherein M is a lanthanide metal.

8. The method of claim 7 wherein M is Gd.

9. The method of claim 6 wherein the fullerene is an endohedral M@C60 class fullerene and M is a radioactive element.

10. The method of claim 6 wherein the at least moderately polar aprotic solvent is selected from the group consisting of:

aliphatic ethers, aryl ethers, cyclic ethers, halogenated alkanes, halogenated benzenes, dialkylsulfoxides and miscible combinations thereof.

11. The method of claim 10 wherein the at least moderately polar aprotic solvent is selected from the group consisting of dichloromethane, tetrachloroethane, ortho-dichlorobenzene, halobenzenes and miscible combinations thereof.

19. The method of claim 6 wherein the solid fullerene is provided in powdered form.

20. The method of claim 6 conducted at ambient temperature.

27. The method of claim 6 wherein the at least moderately polar solvent is dichloromethane or a halogenated benzene.

12. A method for derivatizing fullerenes comprising the steps of:

providing one or more fullerenes as a solid; and

contacting the fullerene solid with a solution comprising an at least moderately polar aprotic solvent in which the one or more fullerenes are soluble at a level of about 0.001 mg/mL or less, a suitable base, and a cyclopropanation reagent, wherein the solvent is tetrahydrofuran, 1,4-dioxane or dimethoxyethane.

13. The method of claim 12 wherein a mixture of fullerenes is derivatized.

14. The method of claim 12 wherein the one or more fullerenes is a giant fullerene.

15. The method of claim 12 wherein the one or more fullerenes is a metal-carbon nanoencapsulate.

16. The method of claim 12 wherein the step of contacting is carried out in an air-free environment.

17. The method of claim 12 wherein an excess of cyclopropanation reagent and base are added.

18. The method of claim 12 wherein the solvent is tetrahydrofuran.

28. The method of claim 12 wherein the one or more fullerenes are selected from the group consisting of endohedral fullerenes, endohedral metallofullerenes, empty C2n small bandgap fullerenes, giant fullerenes, metal-carbon nanoencapsulates and carbon nanotubes.

33. The method of claim 12 wherein the one or more fullerenes are selected from an empty small bandgap fullerene, a giant fullerene, a metal-carbon nanoencapsulate, an endohedral M@C60 class fullerene where

M is an element selected from the group consisting of lanthanide metals, actinide metals, transition metals, alkali metals, and alkaline earth metals.

34. The method of claim 12 wherein the one or more fullerenes are selected from an empty small bandgap fullerene, or an endohedral M@C60 class fullerene where M is an element selected from the group consisting of lanthanide metals, actinide metals, transition metals, alkali metals, and alkaline earth metals.

21. A method for derivatizing fullerenes comprising the steps of:

providing one or more fullerenes as a solid; and

contacting the fullerene solid with a solution comprising an at least moderately polar aprotic solvent in which the one or more fullerenes are soluble at a level of about 0.001 mg/mL or less, a suitable base, and a cyclopropanation reagent, wherein the one or more fullerenes are insoluble fullerenes, wherein the cyclopropanation reagent has two or more cyclopropanation reaction groups cojoined in one molecule.

22. The method of claim 21 wherein the two or more cyclopropanation groups of the same cyclopropanation reagent molecule react with more than one fullerene molecule.

23. A method for derivatizing fullerenes comprising the steps of:

providing one or more fullerenes as a solid; and

contacting the fullerene solid with a solution comprising an at least moderately polar aprotic solvent in which the one or more fullerenes are soluble at a level of about 0.001 mg/mL or less, a suitable base, and a cyclopropanation reagent

wherein the cyclopropanation reagent is a cyclo-[n]-alkylmalonate which is substituted with a leaving group at the alpha carbon of one or more malonate moieties in the reagent.

24. The method of claim 23 wherein the cyclopropanation reagent is a cyclo-[n]-octylmalonate which is substituted with a leaving group at the alpha carbon of one or more malonate moieties in the reagent.

25. The method of claim 23 wherein the at least moderately polar aprotic solvent is selected from the group consisting of aliphatic ethers, aryl ethers, cyclic ethers, halogenated alkanes, halogenated aryls, dimethylsulfoxide and miscible combinations thereof.

26. The method of claim 23 wherein the one or more fullerenes are selected from the group consisting of endohedral metallofullerenes, empty C2n small bandgap fullerenes, giant fullerenes, metal-carbon nanoencapsulates and carbon nanotubes.

29. A method for purification of one or more fullerenes from a mixture which comprises the one or more fullerenes to be purified and non-fullerenic carbonaceous material, which method comprises the steps of:

providing the mixture comprising the one or more fullerenes as a solid, reacting the mixture comprising the one or more fullerenes with a suitable base, and a cyclopropanation reagent in an at least moderately polar aprotic solvent in which the one or more fullerenes to be purified are soluble at a level of about 0.001 mg/mL or less until the one or more fullerenes are derivatized and are soluble in the moderately polar aprotic solvent;

separating the one or more solublized derivatized fullerenes from any non-soluble fullerenes, non-soluble non-fullerenic carbonaceous material or both; and

treating the one or more separated solubilized derivatized fullerenes to remove the groups added by reaction with the cyclopropanation reagent to regenerate the one or more non-derivatized fullerenes, wherein the one or more fullerenes to be purified are insoluble fullerenes, wherein the insoluble fullerenes are selected from an empty small bandgap fullerene, a giant fullerene, a metal-carbon nanoencapsulate, an endohedral M@C60 class fullerene where M is an element selected from the group consisting of lanthanide metals, actinide metals, transition metals, alkali metals, and alkaline earth metals.

30. The method of claim 29 wherein the at least moderately polar aprotic solvent is selected from the group consisting of aliphatic ethers, aryl ethers, cyclic ethers, dialkylsulfoxides and miscible combinations thereof.

31. The method of claim 29 wherein the at least moderately polar aprotic solvent is a non-halogenated polar solvent.

32. The method of claim 29 wherein the cyclopropanation reagent has the formula: