反应 #3704039
相关文献 (1)
openreactiondata ↗doi:10.6084/m9.figshare.5104873.v1; patent:US06127536
反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.
实验步骤: Wet diazide 18 is then dissolved in ethanol and hydrogenated using palladium on charcoal as the catalyst. The reaction is monitored by IR spectroscopy to verify complete reduction of the azido groups. After hydrogenation is complete, the catalyst is filtered off and the filtrate is dried on a rotary evaporator and under high vacuum to give 1,2-bis(2-amino-2-methylpropanamido)benzene (diamine 20) in 100% crude yield (95% purity by NMR=95% yield) from dibromide 16. This product may be used as is, or may be purified by recrystallization from isopropyl alcohol to obtain an analytical sample. In contrast, Collins et al. report a 57% yield for the comparable sequence of the two steps of azide formation and hydrogenation for their synthesis. As indicated earlier, the substantial increase in yield for this two step sequence may be due to the relatively high purity of the dibromide 16 used, which is a direct result of the use of THF as a precipitate-forcing solvent during formation of the dibromide 16. It will be apparent to those with ordinary skill in the art that methods other than hydrogenation with a platinum group metal, e.g., reduction with ammonium sulfide, might be employed for reduction of the azido groups. the catalyst is filtered off the filtrate is dried on a rotary evaporator and under high vacuum
来源 ID: ord-95c5b41e0ebc469ab5d659720beab8fd