Auto-Tandem Catalysis with Ruthenium: From <i>o</i>
-Aminobenzamides and Allylic Alcohols to Quinazolinones <i>via</i>
Redox Isomerization/Acceptorless Dehydrogenation
作者:Weikang Zhang、Chong Meng、Yan Liu、Yawen Tang、Feng Li
DOI:10.1002/adsc.201800660
日期:2018.10.4
A strategy for the synthesis of quinazolinonesvia Ru‐catalyzed redoxisomerization/acceptorlessdehydrogenation was proposed and accomplished. In the presence of a commercially available [(p‐cymene)Cl2]2, a range of desirable products were obtained with o‐aminobenzamides and allylicalcohols as starting materials in moderate to high yields. This strategy is attractive due to high atom efficiency,
Quinazolin-4(3H)-ones and 5,6-Dihydropyrimidin-4(3H)-ones from β-Aminoamides and Orthoesters
作者:Joshua Gavin、Joel Annor-Gyamfi、Richard Bunce
DOI:10.3390/molecules23112925
日期:——
pressure tube conditions with 3 equivalents each of the orthoester and acetic acid in ethanol at 110 °C for 12–72 h. The reaction was tolerant towards functionality on the benzamide and a range of structures was accessible. Workup involved removal of the solvent under vacuum and either recrystallization from ethanol or trituration with ether-pentane. Several 5,6-dihydropyrimidin-4(3H)-ones were also prepared
A visible-light-induced photoredoxMiniscialkylation reaction of N-heteroarenes with ethyl acetate has been reported. The low-toxic ethyl acetate was used for the first time as an alkylation reagent. Hence, 4-quinazolinones, quinolines and pyridines reacted smoothly in the current reaction system. Mechanistic studies indicate that LiBr plays a key role to dramatically improve the efficiency of the
A tandem synthesis of quinazolinones from 2-aminobenzonitriles is demonstrated here by using an aliphatic alcohol-water system. For this transformation, a cheap and easily available cobalt salt and P(CH2CH2PPh2)(3)(PP3) ligand were employed. The substrate scope, scalability, and synthesis of natural products exhibited the vitality of this protocol.