Production of 4-alkoxy-3-pyrrolin-2-on-1-yl acetic acid alkyl esters
申请人:Lonza Ltd.
公开号:US04780545A1
公开(公告)日:1988-10-25
4-Alkoxy-3-pyrrolin-2-on-1-yl acetic acid alkyl esters are intermediate products for the production of cerebrally-active pharmaceutical products. The advantageous process for production of the new intermediate products is described.
Process for the production of 4-hydroxy-2-oxo-pyrrolidin-1-yl acetamide
申请人:Lonza Ltd.
公开号:US04824966A1
公开(公告)日:1989-04-25
Process for the production of 4-hydroxy-2-oxo-pyrrolidin-1-yl acetamide. A 4-(C.sub.1 -C.sub.2)-alkoxy-3-pyrrolin-2-on-1-yl-acetic acid (C.sub.1 -C.sub.4)-alkyl ester of the formula: ##STR1## wherein R.sub.1 is alkyl having 1 or 2 C atoms and R.sub.2 is alkyl having 1 to 4 C atoms, is reacted with either trichloromethylsilane in the presence of an alkali iodide or in an acid anhydrous medium to a 2,4-dioxo-pyrrolidin-1-yl-acetic acid (C.sub.1 -C.sub.4)-alkyl ester. The latter is optionally isolated and then hydrogenated with sodium borohydride to a 4-hydroxy-2-oxo-pyrrolidin-1-yl-acetic acid (C.sub.1 -C.sub.4)-alkyl ester. Finally, the 4-hydroxy-2-oxo-pyrrolidin-1-yl-acetic acid (C.sub.1 -C.sub.4)-alkyl ester is converted by amidation with ammonia to the desired end product.
Methyl (<i>E</i>)-4-Chloro-3-methoxy-2-butenoate: An Extremely Versatile Four Carbon Building Block
作者:Laurent Duc、John F. Mcgarrity、Thomas Meul、Aleksander Warm
DOI:10.1055/s-1992-26120
日期:——
Methyl (E)-4-chloro-3-methoxy-2-butenoate (3a) is inexpensively prepared from methyl 4-chloroacetoacetate using thionyl chloride and methanol on an industrial scale. Many nucleophilic substitution reactions of chloride, which are impossible with the unprotected parent compound proceed readily with 3a.
4-Alkoxy-3-pyrrolin-2-on-1-yl acetic acid alkyl esters are intermediate products for the production of cerebrally-active pharmaceutical products. The advantageous process for production of the new intermediate products is described.