Process Development for the Synthesis of Monocyclic β-Lactam Core 17

Autor: David C. Boyles, Jianmin Sun, Joel T. Arcari, Matthew Frank Brown, Yong Tao, Susan C. Lilley, Jeremy T. Starr, Manjinder S. Lall, Andrew Morgan Stewart, Mark J. Mitton-Fry, David B. Damon
Rok vydání: 2018
Předmět:
Zdroj: Organic Process Research & Development. 22:212-218
ISSN: 1520-586X
1083-6160
DOI: 10.1021/acs.oprd.7b00359
Popis: Process development and multikilogram synthesis of the monocyclic β-lactam core 17 for a novel pyridone-conjugated monobactam antibiotic is described. Starting with commercially available 2-(2,2-diethoxyethyl)isoindoline-1,3-dione, the five-step synthesis features several telescoped operations and direct isolations to provide significant improvement in throughput and reduced solvent usage over initial scale-up campaigns. A particular highlight in this effort includes the development of an efficient Staudinger ketene–imine [2 + 2] cycloaddition reaction of N-Boc-glycine ketene 12 and imine 9 to form racemic β-lactam 13 in good isolated yield (66%) and purity (97%). Another key feature in the synthesis involves a classical resolution of racemic amine 15 to afford single enantiomer salt 17 in excellent isolated yield (45%) with high enantiomeric excess (98%).
Databáze: OpenAIRE