2 results about "Para-nitrobenzaldehyde" patented technology

This invention discloses a Pd nanodendritic structure, its preparation method, and its application. The preparation method includes cutting a glass slide into cubes and washing it; dissolving 1-butylpyridine chloride in chloroform solution, then adding 1-naphthol, and dissolving to prepare a chloroform mixture as the oil phase in the reaction system; preparing a precursor solution as the aqueous phase in the reaction system; placing the glass slide in a cylindrical vial for later use; adding the chloroform mixture to the vial, then adding the precursor solution to form an oil-water two-phase reaction system, and allowing the reaction to stand; extracting the organic phase, transferring the product onto the glass slide, then extracting the aqueous solution, loading the obtained product onto the glass slide, washing and drying it to prepare a Pd nanodendritic structure loaded on a glass slide. The catalyst prepared by this invention through a simple and efficient oil-water interface synthesis method exhibits excellent catalytic activity and selectivity in the selective hydrogenation of p-nitrobenzaldehyde to p-aminobenzaldehyde.

This invention relates to a chiral preparation method for chloramphenicol. Specifically, the method uses p-nitrobenzaldehyde and glycine ester as starting materials, and an asymmetric aldol reaction occurs under the action of a pyridinium salt carbonyl catalyst. Following reduction and amidation reactions, chloramphenicol is obtained. Compared with existing technologies, this invention utilizes the strong catalytic ability of small-molecule pyridinium salt carbonyl catalysts, starting from inexpensive and readily available raw materials, to efficiently control the stereoselectivity of the aldol reaction, and to obtain the desired stereoconfiguration product, chloramphenicol, in a single dose. The preparation method of this invention reduces the protection of active groups, shortens the chiral synthetic route of chloramphenicol, is simple to operate, and is environmentally friendly.