Fuel Markers and Methods of Producing and Using Same
A composition comprising a fuel and at least one compound characterized by Formula I: wherein X is carbon, oxygen, or sulfur; R 1 and R 2 each independently are hydrogen, a C 1 to C 20 alkyl, or a C 6 to C 10 aryl; R 3 and R 3′ each independently are hydrogen or a C 1 to C 4 alkyl; R 4 and R 4′ each independently are hydrogen, a C 1 to C 4 alkyl, a C 4 to C 10 cycloalkyl, or a C 6 to C 10 aryl; R 5 and R 5′ each independently are a C 4 to C 10 alkyl; R 6 and R 6′ each independently are hydrogen or a C 1 to C 6 alkyl; and R 7 and R 7′ each independently are hydrogen or a C 1 to C 4 alkyl; and wherein the compound of Formula I when subjected to GC-MS using electron ionization at greater than about 70 eV produces at least one ion having a mass-to-charge ratio of from 300 to 600.
1 . A compound characterized by Formula I:
wherein X can be carbon (C), oxygen (O), or sulfur (S); R 1 and R 2 can each independently be hydrogen, a C 1 to C 20 alkyl group, or a C 6 to C 10 aryl group; R 3 and R 3′ can each independently be hydrogen or a C 1 to C 4 alkyl group; R 4 and R 4′ can each independently be hydrogen, a C 1 to C 4 alkyl group, a C 4 to C 10 cycloalkyl group, or a C 6 to C 10 aryl group; R 5 and R 5′ can each independently be a C 4 to C 10 alkyl group; R 6 and R 6′ can each independently be hydrogen or a C 1 to C 6 alkyl group; and R 7 and R 7′ can each independently be hydrogen or a C 1 to C 4 alkyl group; and wherein the compound characterized by Formula I when subjected to gas chromatography-mass spectrometry (GC-MS) using electron ionization produces at least one ion having a mass-to-charge ratio of greater than about 300 at an ionization energy of equal to or greater than about 70 eV.
2 . The compound of claim 1 wherein X is O or S and R 1 and R 2 are lone non-bonding electron pairs.
3 . The compound of claim 1 wherein the compound characterized by Formula I has Structure A:
4 . The compound of claim 1 wherein the compound characterized by Formula I has Structures B-F:
5 . The compound of claim 1 wherein X is C and R 1 and R 2 each independently are selected from the group consisting of a methyl group, an ethyl group, a n-propyl group, an iso-propyl group, a n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a n-pentyl group, an iso-pentyl group, a sec-pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group and a nonadecyl group.
6 . The compound of claim 1 wherein the compound characterized by Formula I has any of Structures G-O:
7 . The compound of claim 1 wherein X is C and R 1 and R 2 can each independently be hydrogen, a C 1 to C 10 alkyl group, or a C 6 to C 10 aryl group.
8 . The compound of claim 7 wherein the C 6 to C 10 aryl group is phenyl, a substituted phenyl, tolyl, a substituted tolyl, xylyl or a substituted xylyl.
9 . The compound of claim 7 wherein the compound characterized by Formula I has Structure P:
10 . The compound of claim 1 wherein X is C and R 3 and R 3′ can each independently be a methyl group or hydrogen.
11 . The compound of claim 1 wherein X is C and R 4 and R 4′ can each independently be a C 1 to C 4 alkyl group, a C 4 to C 10 cycloalkyl group, or a C 6 to C 10 aryl group.
12 . The compound of claim 11 wherein the C 4 to C 10 cycloalkyl group is a cyclobutyl group, a substituted cyclobutyl group, a cyclopentyl group, a substituted cyclopentyl group, a cyclohexyl group, a substituted cyclohexyl group, a cycloheptyl group, a substituted cycloheptyl group, a cyclooctyl group, or a substituted cyclooctyl group.
13 . The compound of claim 1 wherein R 4 and R 4′ are hydrogen.
14 . The compound of claim 1 wherein R 4 and R 4′ can each independently be hydrogen or a tert-butyl group.
15 . The compound of claim 1 wherein X is C, R 1 and R 2 are a methyl group, and R 5 and R 5′ are both a C 4 to C 10 alkyl group.
16 . The compound of claim 1 wherein R 5 and R 5′ are both a pentyl group or a heptyl group.
17 . The compound of claim 1 wherein R 6 and R 6′ each independently are selected from the group consisting of a methyl group, an ethyl group, a n-propyl group, an iso-propyl group, a n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a n-pentyl group, an iso-pentyl group, a sec-pentyl group and a hexyl group.
18 . The compound of claim 1 wherein X is O and R 5 and R 5′ are a heptyl group.
19 . The compound of claim 1 wherein X is O or S and R 3 , R 3′ , R 7 and R 7′ can each independently be hydrogen or a methyl group.
20 . The compound of claim 1 wherein the compound characterized by Formula I is soluble in a solvent characterized by a flash point greater than about 60° C.; wherein the solvent is miscible with a fuel; and wherein the compound characterized by Formula I is characterized by a solubility in the solvent of equal to or greater than about 50% at 25° C.