Provided is a method for producing an α-azidoaniline derivative or an α,α′-diazide derivative using an aniline derivative as a starting material that includes a method for producing an α-azidoaniline derivative or an α,α′-diazide derivative represented by Formula (2), including the step of: contacting an aniline derivative represented by Formula (1) with an azidating agent in presence of water, a persulfate, and a copper compound.

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Provided is a method for producing an α-azidoaniline derivative or an α,α′-diazide derivative using an aniline derivative as a starting material that includes a method for producing an α-azidoaniline derivative or an α,α′-diazide derivative represented by Formula (2), including the step of: contacting an aniline derivative represented by Formula (1) with an azidating agent in presence of water, a persulfate, and a copper compound.

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Embodiments of the present disclosure are related to improved processes for making L-ornithine phenylacetate without using any silver salts or forming any L-ornithine intermediate salts, such as a benzoate salt. The present processes may be used in the commercial scale manufacturing of L-ornithine phenylacetate with high yields and low impurities.

Embodiments of the present disclosure are related to improved processes for making L-ornithine phenylacetate without using any silver salts or forming any L-ornithine intermediate salts, such as a benzoate salt. The present processes may be used in the commercial scale manufacturing of L-ornithine phenylacetate with high yields and low impurities.

Disclosed herein are improved methods for the synthesis of zinc-amino acid-halide complexes via reaction of zinc halide and amino acid free base in a solvent comprising a polyol, as well as oral care compositions comprising said complexes made according to said method.

Disclosed herein are improved methods for the synthesis of zinc-amino acid-halide complexes via reaction of zinc halide and amino acid free base in a solvent comprising a polyol, as well as oral care compositions comprising said complexes made according to said method.

Provided is a method of preparing L-homoserine, the method including contacting an L-homoserine derivative with a solid acid catalyst.

Provided is a method of preparing L-homoserine, the method including contacting an L-homoserine derivative with a solid acid catalyst.

Disclosed herein are improved methods for the synthesis of zinc-amino acid-halide complexes via reaction of zinc oxide and amino acid hydrochloride in a solvent comprising a polyol, as well as oral care compositions comprising said complexes made according to said method.

Disclosed herein are improved methods for the synthesis of zinc-amino acid-halide complexes via reaction of zinc oxide and amino acid hydrochloride in a solvent comprising a polyol, as well as oral care compositions comprising said complexes made according to said method.