Intermediate for preparing diazepam D5 and diazepam D8 and preparation method thereof

The invention discloses intermediate for preparing diazepam D5 and diazepam D8 and preparation method thereof; with the methyl 4H 3 of 6 chlorine 2; the ketone of 1 benzoxazine 4 is raw material; through reacting, hydrolyzing, acylated, cyclization with deuterated bromobenzene RMgBr; isolate and purify to obtain (the phenyl d of 7 chlorine of intermediate, 1,3 dihydro 5 for preparing diazepam D5 and diazepam D8 5 ) 1,4 benzodiazepines of 2H, 2 ketone.Present invention process has that reaction condition is gentle, simple to operate etc. a little the deuterated diazepam intermediate prepared using the present invention, chemical purity is high, and good product quality, stability is good, available for preparing diazepam D 5 Standard items, it can also be used to prepare diazepam D 8 Standard items and other related deuterated thing standard items.