No abstract

Simple, efficient, and scalable syntheses of 3-hydroxy-1,4benzodiazepines, oxazepam (1), and lorazepam (2) were developed. The syntheses are based on the new acetoxylation reaction of the 3-position of the 1,4-benzodiazepine ring. The reaction involves iodine (20-50 mol %)-catalyzed acetoxylation in the presence of potassium acetate (2 equiv) and potassium peroxydisulfate (1-2 equiv) as a stoichiometric oxidant affording the corresponding 3-acetoxy-1,4-benzodiazepines in good-to-high yields. The latter were converted by selective saponification to 3-hydroxy-1,4-benzodiazepines of very high purity (>99.8%) in an overall yield of 83% (oxazepam) and 64% (lorazepam).

No abstract

Ammonium carbamate can be used as a very effective reagent for preparation of different substituted b-amino-a,b-unsaturated esters in methanol at room temperature. The product is isolated without aqueous work-up in high purity and excellent yield. The method is simple and easily scaled-up.

Polyphenyl derivatives Q 0700Copper (I)-Catalyzed Homocoupling of Aryldiazonium Salts: Synthesis of Symmetrical Biaryls. -The first applicable protocols for the preparation of symmetrical biaryls from aryldiazonium salts are developed. -(CEPANEC*, I.; LITVIC, M.; UDIKOVIC, J.; POGORELIC, I.; LOVRIC, M.; Tetrahedron 63 (2007) 25, 5614-5621; Res. Dep., BELUPO Pharm. Cosmet., Inc., HR-10000 Zagreb, Croatia; Eng.) -Nuesgen 40-095