3-Fluoro-1-H-1,5-benzodiazepine-2,4-dione
o-Phenylenediamine (2.70 g, 25 mmol) was added to the solution of sodium (1.2 g, 53 mmol) in anhydrous ethanol (50 mL) and the mixture was heated to reflux. Diethyl 2-fluoromalonate (4.45 g, 25 mmol) was added dropwise over 10 minutes and the mixture was heated at reflux for 2 h. After cooling to room temperature, the solution was filtered, the residue was washed with ethanol (20 mL), dissolved in water (30 mL) and acidified with HCl to pH 1. The mixture was cooled in ice, filtered, washed with water (2 × 10mL) and dried in vacuo to afford 3-fluoro-1-H-1,5-benzodiazepine-2,4-dione (3.23 g, 68%) as a tan powder.
m.p.: >300 °C, ([M + H]+, 195.0567, C9H8FN2O2 requires: [M]+, 195.0570);
IR (neat,cm−1) 3084, 2951, 1727, 1681, 1500, 1159;
δH (DMSO d6, 400 MHz): 5.57 (1H, d, 2JHF 46.4, CHF), 7.15–7.19 (2H, m, Ar–H), 7.22 (2H, dt, 3JHH 6.6, 4JHH 3.5, Ar–H), 10.81 (2H, bs N–H); δF (DMSO d6, 376 MHz): – 207.99 (d, 2JHF 46.4 C–F);
δC (DMSO d6, 100 MHz) 85.12 (d, 1JCF 184.5, C–F), 122.55, 125.52, 128.41, 163.36 (d, 2JCF 23.2, CO), 164.59 (d, 2JCF 13.4, CO);
m/z (ASAP) 195 (100%, [M + H]+), 135 (23%, [M − COCHF]+)............ N. Ishikawa, A. Takaoka and M. K. Ibrahim, J. Fluorine Chem., 1984, 25, 203–212 CrossRef CAS.
http://pubs.rsc.org/en/content/articlehtml/2015/gc/c5gc00402k
DRUG APPROVALS BY DR ANTHONY MELVIN CRASTO .....FOR BLOG HOME CLICK HERE
amcrasto@gmail.com
///