- Alumina supported 12-tungstophosphoric acid as an efficient and reusable catalyst for synthesis of 1,5-benzodiazepines
-
Alumina supported 12-tungstophosphoric acid catalyzes efficiently the reaction of o-phenylenediamine with ketones under solvent-free condition to afford the corresponding 1,5-benzodiazepines in good to excellent yields. The catalyst can be recovered and r
- Abdollahi-Alibeik, Mohammad,Zaghaghi, Zahra,Mohammadpoor-Baltork, Iraj
-
-
Read Online
- Electrochemical oxidation of o-phenylenediamine and 1,3 dihydrospiro[benzo[d]imidazole-2,1′-cyclohexane]. A comprehensive study and introducing a novel case of CE mechanism
-
Electrochemical behavior of o-phenylenediamine (PDA) and 1,3-dihydrospiro[benzo[d]imidazole-2,1′-cyclohexane] (DBI) was extensively studied in water and water/ethanol mixture using different voltammetric techniques. Our data showed that the oxidation of P
- Khoram, Mahmood Masoudi,Nematollahi, Davood,Rahimi, Abdollah,Zivari-Moshfegh, Faezeh
-
-
Read Online
- Reactions of fluoroalkyl-containing lithium 1,3-diketonates with diaminoarenes and 2-aminobenzenethiol
-
1,5-Benzo[b]- and 1,5-naphtho[2,3-b]diazepines were synthesized by the reaction of lithium 1,3-diketonates with 1,2-diaminobenzene and 2,3-diaminonaphthalene in an MeOH-AcOH-HCl mixture at 0°C. The reactions of fluoroalkyl-containing lithium 1,3-diketonates with 1,2-diaminobenzene and 1,2-diamino-4,5-difluorobenzene under reflux in acetic acid afford 2-fluoroalkyl-containing benzimidazoles as the major products, whereas the reaction with 2-aminothiophenol gives 2-phenylbenzothiazole. The reactions of lithium diketonate containing the cyclohexane and cyclopentane moieties with 1,2-diaminoarenes and 2-aminobenzenethiol are accompanied by the opening of the carbocycle to form 2-(6-oxo-7,7,7-trifluoroheptyl)benzimidazole and 2-(5-oxo-6,6,6-trifluorohexyl)benzothiazole hydrates, respectively.
- Filyakova,Boltacheva,Sevenard,Charushina
-
experimental part
p. 1791 - 1796
(2011/05/07)
-
- Rearrangement of spiro-benzimidazolines: preparation of N-alkenyl- and N-alkyl-benzimidazol-2-ones
-
A synthetically useful protocol has been developed for the preparation of highly functionalized N-alkenyl-benzimidazol-2-ones. Reaction of commercially available o-phenylenediamines with variously substituted cyclic ketones provides spiro-benzimidazolines. Treatment of these spiro-benzimidazolines with triphosgene in the presence of potassium carbonate results in rapid rearrangement and formation of N-alkenyl-benzimidazol-2-ones in modest to excellent yield for the two-step sequence. Extension of this methodology toward the preparation of a μ opiate receptor antagonist and droperidol, a potent antiemetic and antipsychotic agent, currently a marketed pharmaceutical is also described. Upon treatment of spiro-benzimidazolines with triphosgene in the presence of sodium triacetoxyborohydride, N-alkyl-benzimidazol-2-ones were formed.
- Kuethe, Jeffrey T.,Varon, Jack,Childers, Karla G.
-
p. 11489 - 11502
(2008/03/13)
-