A method is provided for preparing a fuel additive having the formula: (1) The method comprises carrying out the following reactions: (i) addition of an alkylating agent b to starting material a: (a) to form an intermediate c; and (ii) ring closing intermediate c to form fuel additive e.

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An optimised method for preparing a fuel additive f is provided. The method comprises carrying out the following reaction: (c, d, e) Starting material c may be prepared using an optimised method which comprises carrying out the following reaction: (a, b, c)

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An optimised method for preparing a fuel additive f is provided. The method comprises carrying out the following reaction: (c, d, e) Starting material c may be prepared using an optimised method which comprises carrying out the following reaction: (a, b, c)

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A method for preparing a fuel additive d is provided. The method comprises carrying out the following reaction: (1) The fuel additive d may be used as an octane-boosting additive in a fuel for a spark, ignition internal combustion engine.

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A method for preparing a fuel additive d is provided. The method comprises carrying out the following reaction: (1) The fuel additive d may be used as an octane-boosting additive in a fuel for a spark, ignition internal combustion engine.

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Methods for preparing an octane-boosting fuel additive having the following formula: are provided. In a first aspect, the method may comprise carrying out the following reaction: (i), (ii) In a second aspect, the method may comprise: (1) preparing the fuel additive; and (2) purifying the product of step (1) by: (a) dissolving the fuel additive in a water-insoluble solvent to form a solution; (b) washing the solution with water; and (c) separating the fuel additive product from the water-insoluble solvent using distillation. Steps (i) and (1) of the methods are carried out in the presence of butylated hydroxytoluene.

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Methods for preparing an octane-boosting fuel additive having the following formula: are provided. In a first aspect, the method may comprise carrying out the following reaction: (i), (ii) In a second aspect, the method may comprise: (1) preparing the fuel additive; and (2) purifying the product of step (1) by: (a) dissolving the fuel additive in a water-insoluble solvent to form a solution; (b) washing the solution with water; and (c) separating the fuel additive product from the water-insoluble solvent using distillation. Steps (i) and (1) of the methods are carried out in the presence of butylated hydroxytoluene.

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A method for preparing a substituted fuel additive d is provided. The method comprises carrying out the following reaction: (a) (b) (d), The fuel additive d may be used as an octane-boosting additive in a fuel for a spark-ignition internal combustion engine.

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A method for preparing a substituted fuel additive d is provided. The method comprises carrying out the following reaction: (a) (b) (d), The fuel additive d may be used as an octane-boosting additive in a fuel for a spark-ignition internal combustion engine.

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A fuel additive composition has a base fuel; colloidal nanocarbon particles, and a dispersion stabilizer that aids in stably suspending the colloidal nanocarbon particles in the base fuel. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.