Lubricants for magnetic recording media

An intermediate compound of formula (IIa) or (IIb)

• wherein
• n in formula (IIa) or (IIb) is 4 or 5;
• m in formula (IIa) or (IIb) is 0, 1, 2, 3, or 4;
• each R′, when present, is a different or a same substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 perfluorinated alkyl, C1-C10 perfluorinated alkoxy, and F.

A method for forming the intermediate compound of formula (IIa) or (IIb)

• wherein
• n in formula (IIa) or (IIb) is 4 or 5;
• m in formula (IIa) or (IIb) is 0, 1, 2, 3, or 4;
• each R′, when present, is a different or a same substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 perfluorinated alkyl, C1-C10 perfluorinated alkoxy, and F,
• the method comprising:
• reacting hexachlorocyclotriphosphazene with a phenoxide of formula (IIIa) or (IIIb)
• in a tetrahydrofuran solvent to form the intermediate compound of formula (IIa) or (IIb), respectively.

A method for forming the compound of formula (I)

• wherein
• n in formula (I) is 0, 1, 2, 3, or 4;
• m in formula (I) is 0, 1, 2, 3, or 4;
• each R′, when present, is a different or a same substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 perfluorinated alkyl, C1-C10 perfluorinated alkoxy, and F;
• each OArf is a different or a same fluorinated C6-C20 aryloxy group;
• and
• Rf is selected from the group consisting of CF2CF2O(CF2CF2CF2O)rCF2CF2 wherein r is 2 to 30 and CF2(OCF2CF2)sO(CF2)t wherein s is 2 to 30 and t is 0, 1, 2, or 3, the method comprising:
• reacting the intermediate compound of formula (IIa) or (IIb) with NaOArf and NaOCH2—Rf—CF3 in a tetrahydrofuran solvent,
• wherein
• n in formula (IIa) or (I %) is 4 or 5;
• m in formula (IIa) or (IIb) is 0, 1, 2, 3, or 4;
• each R′, when present, is a different or a same substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 perfluorinated alkyl, C1-C10 perfluorinated alkoxy, and F;
• OArf in NaOArf is a fluorinated C6-C20 aryloxy group;
• and
• Rf is defined above.

A method for lubricating a magnetic recording medium, comprising applying a lubricant comprising a compound of formula (I)

• wherein
• n in formula (I) is 0, 1, 2, 3, or 4;
• m in formula (I) is 0, 1, 2, 3, or 4;
• each R′, when present, is a different or a same substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 perfluorinated alkyl, C1-C10 perfluorinated alkoxy, and F;
• each OArf is a different or a same fluorinated C6-C20 aryloxy group;
• and
• Rf is selected from the group consisting of CF2CF2O(CF2CF2CF2O)rCF2CF2 wherein r is 2 to 30 and CF2(OCF2CF2)sO(CF2)t wherein s is 2 to 30 and t is 0, 1, 2, or 3.