Conversion of the laboratory synthetic route of the N-aryl-2-benzothiazolamine R116010 to a manufacturing method

Citation
W. Aelterman et al., Conversion of the laboratory synthetic route of the N-aryl-2-benzothiazolamine R116010 to a manufacturing method, ORG PROC R, 5(5), 2001, pp. 467-471
Citations number
21
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
ORGANIC PROCESS RESEARCH & DEVELOPMENT
ISSN journal
10836160 → ACNP
Volume
5
Issue
5
Year of publication
2001
Pages
467 - 471
Database
ISI
SICI code
1083-6160(200109/10)5:5<467:COTLSR>2.0.ZU;2-O
Abstract
A facile and large-scale preparation of the antitumor agent R116010 has bee n developed. The new synthetic process requires four steps: (i) Friedel-Cra fts reaction of N-phenyl-2-benzothiazolamine with 2-chloropropionyl chlorid e, (ii) conversion of the alpha -chloroketone into the corresponding alpha- (dimethylamino)ketone and resolution of the latter, (iii) reduction of the chiral aminoketone with resultant formation of the beta -amino alcohol and finally (iv) conversion of the amino alcohol into the beta -aminoiniidazole R116010. The key strategic improvement is the crystallization-induced dias tereomeric dynamic resolution of the aminoketone, leading to the chiral ket one in 90% yield and 90% enantiomeric purity. This new process improves the overall yield from 0.26 to 18.8% without tedious chromatographic separatio ns and hazardous reaction conditions.