Mild and efficient reduction of azides to amines: synthesis of fused [2,1-b]quinazolinones

Eco‐friendly and Efficient Synthesis of 2,3‐Dihydroquinazolin‐4(1H)‐ones

“…1 In particular dihydroquinazolin-4(1H)-one scaffolds were found as a core unit in a number of biologically active compounds that include anticancer, antidituric, and anticonvulsant activities. 1 Literature survey showed that several methods in synthesis of quinazolinone derivatives were reported such as cyclization of o-acylaminobenzamides, 2 amidation of 2-aminobenzonitrile followed by oxidative ring closure, 3 solid-phase synthesis of 2-arylaminosubstituted quinazolinones, 4 reduction of the azide functionality, 5 reaction of isatoic anhydrides and Schiff bases, 6 conversion of 2-nitro-N-arylbenzamides to 2,3-dihydroquinazo-lin-4(1H)-ones using SnCl 2 , and Pd-catalyzed heterocyclization of nitroenes. 7 Also, quinazolinones were prepared from a) three-component reactions of isatoic anhydride, primary amine or ammonium acetate and aldehydes in the presence of p-toluenesulfonic acids, 8 24 and chiral phosphoric acids 25 as catalysts.…”

A facial synthesis of quinazolino[1,4]benzodiazepine alkaloids via reductive N-heterocyclization of N-(2-nitrobenzoyl)amides: total synthesis of asperlicin C, circumdatin H, and its analogues

“…15,16 Various methods for the synthesis of alkaloids encompassing a quinazolino [1,4]benzodiazepine moiety in their skeleton have been developed and numerous research papers and several reviews have recently appeared. 1,[17][18][19][20][21][22][23][24][25][26][27] The implementations of 2-azidobenzoylamides in aza-Wittig methodology 6,[28][29][30][31][32][33] and transition metalinduced reductive N-heterocyclization [34][35][36][37][38][39] have emerged as versatile strategies for the construction of a variety of heterocyclic compounds. Although the aza-wittig and metal-induced reductive cyclization procedures afford quinazolino [1,4]benzodiazepines, they have some disadvantages such as cost and availability of the reagents such as 2-azidobenzoyl chloride and transition metals, generation of phosphine oxide by-product, harsh reaction conditions, low atom economy and synthetic practicality.…”

A novel catalyst zinc(II) perfluorooctanoate [Zn(PFO)2]-catalyzed three-component one-pot reaction: Synthesis of quinazolinone derivatives in aqueous micellar media

“…With physiological and pharmacological properties, it implies that the quinazolinone structure have various biological activities, such as anticancer [17], antidituric [18], anticonvulsant [19]. Many literatures had reported several methods for synthesis of quinazolinones, and common synthetic methods for aryl-substituted quinazolinone compounds included cyclization of oacylaminobenzamides [20], amidation of 2-aminobenzonitrile followed by oxidative ring closure [21], solid-phase synthesis of 2-arylamino-substituted quinazolinones [22], reduction of the azide functionality [23], preparation from isatoic anhydrides and Schiff bases [24], and Pd-catalyzed heterocyclization of nitoarenes [25]. All these procedure have certain limitations such as tedious process, long reaction time, harsh reaction conditions, and low yields.…”