The present invention relates to an improved and economical process for enantioselective synthesis and purification of a novel key intermediate of Brivaracetam. Further, the present invention also relates to a process for the preparation of a chirally pure Brivaracetam of formula I utilizing the said intermediate.

##STR00001##

The present invention relates to an improved and economical process for enantioselective synthesis and purification of a novel key intermediate of Brivaracetam. Further, the present invention also relates to a process for the preparation of a chirally pure Brivaracetam of formula I utilizing the said intermediate.

##STR00001##

The present invention relates to a brivaracetam intermediate, a preparation method therefor, and a preparation method for brivaracetam. The steps of the method for preparing brivaracetam described in the present invention are short and the raw materials are cheap, moreover, the method is simple and highly effective without requiring isomer separation by means of column chromatography or asymmetric synthesis, being suitable for industrial large-scale production. In addition, disclosed by the present invention is a compound as shown in formula (II), which may be used for the synthesis of brivaracetam.

##STR00001##

The present invention relates to a brivaracetam intermediate, a preparation method therefor, and a preparation method for brivaracetam. The steps of the method for preparing brivaracetam described in the present invention are short and the raw materials are cheap, moreover, the method is simple and highly effective without requiring isomer separation by means of column chromatography or asymmetric synthesis, being suitable for industrial large-scale production. In addition, disclosed by the present invention is a compound as shown in formula (II), which may be used for the synthesis of brivaracetam.

##STR00001##

The present invention provides a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Adopting a particular isomerization-crystallization condition makes it possible to a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Additionally, an intermediate efficacious for producing lacosamide is provided.

The present invention provides a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Adopting a particular isomerization-crystallization condition makes it possible to a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Additionally, an intermediate efficacious for producing lacosamide is provided.

The present invention provides a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Adopting a particular isomerization-crystallization condition makes it possible to a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Additionally, an intermediate efficacious for producing lacosamide is provided.

A core-shell nanocomposite is formed by co-assembly of an amphiphilic polymer and hydrophobically modified magnetic nanoparticles, with its core being a hydrophobically modified magnetic nanomaterial and its shell being the amphiphilic polymer, wherein hydrophilic segments in the amphiphilic polymer are located at an outermost layer of the shell. The above composite can be used as additives in the crystallization of conglomerates and obtain optically pure crystals of both enantiomers in a single process. The key thereof is that the composite is used to enrich molecules with the same configuration while inhibit the crystallization of the other enantiomer in a supersaturated solution of conglomerates, such that a non-magnetic crystal and a magnetic crystal (which are enantiomers of each other) are generated in a unit operation. Optically pure crystals of both enantiomers with over 90 ee % can be obtained by one-time crystallization, and the total yield can be as high as 40%.

A core-shell nanocomposite is formed by co-assembly of an amphiphilic polymer and hydrophobically modified magnetic nanoparticles, with its core being a hydrophobically modified magnetic nanomaterial and its shell being the amphiphilic polymer, wherein hydrophilic segments in the amphiphilic polymer are located at an outermost layer of the shell. The above composite can be used as additives in the crystallization of conglomerates and obtain optically pure crystals of both enantiomers in a single process. The key thereof is that the composite is used to enrich molecules with the same configuration while inhibit the crystallization of the other enantiomer in a supersaturated solution of conglomerates, such that a non-magnetic crystal and a magnetic crystal (which are enantiomers of each other) are generated in a unit operation. Optically pure crystals of both enantiomers with over 90 ee % can be obtained by one-time crystallization, and the total yield can be as high as 40%.

The present invention provides a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Adopting a particular isomerization-crystallization condition makes it possible to a method of industrially and safely producing lacosamide high in diastereomeric excess at a high yield and a low cost. Additionally, an intermediate efficacious for producing lacosamide is provided.