83541-01-9

Upstream product

• 83477-97-8 methyl 2(R)-hydroxy-3(R)-ethyl-N-(benzyloxy)-succinamate 
• 120419-78-5 (R)-1-Benzyloxy-3-ethyl-4-oxo-azetidine-2-carbaldehyde 
• 120419-76-3 (R)-1-Benzyloxy-3-ethyl-4-((E)-styryl)-azetidin-2-one 
• 16048-75-2 (2R,3R)-2-Ethyl-3-hydroxy-succinic acid 
• 83477-95-6 methyl hydrogen 2(R)-hydroxy-3(R)-ethylsuccinate 

Relevant academic research and scientific papers

TiCl4-MEDIATED REACTIONS OF SILYL KETENE ACETALS DERIVED FROM N-METHYLEPHEDRINE ESTERS: ASYMMETRIC SYNTHESIS OF β-LACTAMS

TiCl4 mediated addition of silyl ketene acetals derived from N-methylephedrine esters to various aldehydes and imines was used as the key-step in the enantio- and diastereo-controlled synthesis of β-lactams.Thus 3,4-trans and cis substituted-2-azetidinone

Enantioselective Syntheses of 3-Substituted 4-(Alkoxycarbonyl)-2-azetidinones from Malic Acid

Enantioselective syntheses of 3-substituted 4-(alkoxycarbonyl)-2-azetidinones from malic acid have been developed.Alkylation of diesters of D-malic acid provided primarily the erythro products 15RS.Base-mediated inversion gave racemic threo isomers 15.Saponification of 15 and selective monoesterification provided the correspondingly substituted β-hydroxy acids 17, which could also be epimerized at the hydroxyl position.Separate conversion of the isomers 17 to the hydroxamates 18 followed by cyclization gave the desired β-lactams 19 with complete control of stereochemistry.