A New and Facile Synthesis of Quinazoline-2,4(1H,3H)-diones

Abstract

A new and facile preparation of quinazoline-2,4(1H,3H)-diones was first reported which was the condensation of aromatic o-aminonitriles with DMF or N,N-diethylformamide in the presence of ZnCl(2) (0.5-10 mol %) at 190-200 degrees C in the sealed reactor.

New conditions for synthesis of (±)‐2‐monosubstituted and (±)‐2,2‐disubstituted 2,3‐dihydro‐4(1H)‐quinazolinones from 2‐nitro‐ and 2‐aminobenzamide

“…This compound was prepared from 415 mg (2.50 mmoles) of 1 , 495 mg (2.50 mmoles) of diphosgene ( 14 ), and 698 mg (12.5 mmoles) of iron powder in 8 mL of acetic acid using the procedure outlined for the preparation of 3a with the reflux period extended to 8 h. Product 9 (348 mg, 86%) was isolated directly from the reaction mixture as a gray solid, mp 343–345°C (ref. 34; mp > 300°C). The spectral data matched those reported previously [ 34].…”

Ionic liquid immobilized onto fibrous nano-silica: A highly active and reusable catalyst for the synthesis of quinazoline-2,4(1H,3H)-diones

“…Synthesis of quinazoline-2,4(1 H,3 H)-diones using CO 2 and 2-aminobenzonitriles as raw materials has attracted considerable interest, and various kinds of catalysts have been used to promote the reactions, such as 1,8-diazabicyclo [5.4.0]undec-7-ene (DBU) [1], Cs 2 CO 3 [2], 1-butyl-3-methylimidazolium hydroxide ([Bmim]OH) [3], MgO/ZrO 2 [4], 1,1,3,3-tetramethylguanidine (TMG) [5], ZnCl 2 [6], [Bmim]Ac [7], and so on. However, these reaction systems are more or less subjected to some drawbacks, such as long reaction time, high pressure of CO 2 , use of organic solvents, and difficulty in recycling the catalysts.…”

Efficient synthesis of 2-arylquinazolines via copper-catalyzed dual oxidative benzylic CH aminations of methylarenes

“…Usually, the traditional synthesis of quinazolines involves reactions of Bischler cyclization, dicarbonyl compounds with diamines and reactions from 2-aminobenzonitriles or anthranilic acids as well as N-arylbenzamides [6][7][8][9]. Our group have been focusing in the synthesis of quinazolines and a variety of excellent approaches to the quinazolines were developed [10][11][12][13].…”