A reagent used to construct substituted 2-azetidinones for further elaboration into annulated β-lactams. Also a commonly employed reagent for asymmetric synthesis of β-lactams.β-内酰胺的非对称合成试剂。 Benzyloxyacetyl chloride was used in preparation of: · (S)-3-(methylamino)-3-((R)-pyrrolidin-3-yl)propanenitrile, key intermediate in the preparation of fluoroquinolone antibiotic for respiratory tract infections · non-racemic helicene · β-lactams A reagent used to construct substituted 2-azetidinones for further elaboration into annulated β-lactams. Also a commonly employed reagent for asymmetric synthesis of β-lactams.