𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Kinetic resolution of diastereomeric racemates of 7-bromo-3-(1′-hydroxyethyl)-1-methyl-5-(2′-pyridyl)-2,3-dihydro-1H-1,4-benzodiazepin-2-one by immobilized CAL-B

✍ Scribed by Maja Majerić Elenkov; Zdenko Hameršak; Vitomir Šunjić

Publisher
Elsevier Science
Year
2003
Tongue
English
Weight
214 KB
Volume
14
Category
Article
ISSN
0957-4166

No coin nor oath required. For personal study only.

✦ Synopsis

Immobilized CAL-B catalyzed kinetic resolution of syn-7-bromo-3-(1%-hydroxyethyl)-1-methyl-5-(2%-pyridyl)-2,3-dihydro-1H-1,4-benzodiazepin-2-one syn-(±)-2 and its anti-diastereomer (±)-3 were achieved with E-values over 200. Completely enantioselective acetylation of (1%R)-enantiomers in diastereomeric racemates with an opposite configuration at the second stereogenic center C(3) occured at substantially different rate (t 1/2syn /t 1/2anti ca. 1/20). Conformational origins of enantioselection are also discussed.

📜 SIMILAR VOLUMES

The synthesis of 7-chloro-1-methyl-5-phe
The synthesis of 7-chloro-1-methyl-5-phenyl-1, 3-dihydro-2H-1,4-benzodiazepin-2-one-5-14C and 7-nitro-1-methyl-5-(2′-fluorophenyl)-1, 3-dihydro-2H-1,4-benzodiazepin-2-one-5-14C
✍ H. H. Kaegi; W. Burger; C. J. Bader 📂 Article 📅 1982 🏛 John Wiley and Sons 🌐 French ⚖ 393 KB 👁 1 views

## Abstract Two benzodiazepines, Diazepam and Flunitrazepam, labeled with carbon‐14 in position 5 of the diazepine ring have been synthesized. Use of a condensation between iminochlorides and ^14^C‐benzonitriles, followed by exhaustive methylation of the resulting quinazolines and hydrolyses is des