Relationships between step and cumulative PMI and E-factors: implications on estimating material efficiency with respect to charting synthesis optimization strategies

Autor: Andraos John
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Green Processing and Synthesis, Vol 8, Iss 1, Pp 324-336 (2019)
Druh dokumentu: article
ISSN: 2191-9550
DOI: 10.1515/gps-2018-0131
Popis: This report describes mathematical relationships between step and cumulative process mass intensities (PMIs) for synthesis plans, and analogous parameters applied to E-factors. It is shown that both step E-factors and step PMIs are not additive for synthesis plans. It is also shown that a recursive calculation of cumulative PMIs from step PMIs is a rapid method of determining overall PMIs for synthesis plans, though cumulative PMIs are not sufficiently informative as step PMIs or step E-factors to identify bottlenecks in synthesis plans. Illustrations on the use of these metrics to track the material efficiency of published synthesis plans for the pharmaceutical, apixaban, are given as a template example. Advantages and disadvantages of each metric are discussed. A general algorithm to select the most promising candidate synthesis plans considered at the design stage for a given molecular target that most likely satisfy “green” material efficiency criteria is also presented.
Databáze: Directory of Open Access Journals