6141-15-7

Upstream product

• 6141-13-5 2-chloroquinazoline 
• 124-41-4 sodium methylate 
• 26260-02-6 2-iodobenzaldehyde 
• 5329-33-9 o-methylisourea hydrochloride 
• 607-68-1 2,4-dichloroquinazoline 
• 187336-12-5 4-(α-methyl-α-hydroxy-p-bromobenzyl)-2-methoxyquinazoline 
• 187336-11-4 2-methoxy-4-(p-bromobenzoyl)quinazoline 
• 187336-10-3 2-chloro-4-(p-bromobenzoyl)quinazoline 

Downstream Products

• 132256-64-5 Phenyl-quinazolin-2-yl-acetonitrile 
• 132256-81-6 phenyl(quinazolin-2-yl)methanone 

Relevant academic research and scientific papers

Mild and efficient ligand-free copper-catalyzed condensation for the synthesis of quinazolines

Condensation of o-iodobenzaldehydes 1a_c with amidine hydrochlorides 2a_p under ligand-free copper-catalyzed Ullmann N-arylation conditions afforded the corresponding quinazolines 3a-r in good to excellent yields.

Carbon-carbon bond cleavage of α-hydroxybenzylheteroarenes catalyzed by cyanide ion: Retro-benzoin condensation affords ketones and heteroarenes and benzyl migration affords benzylheteroarenes and arenecarbaldehydes

4-(α-Benzylα-hydroxybenzyl)quinazoline (4a) underwent retro-benzoin condensation catalyzed by cyanide ion to give deoxybenzoin (2a) and quinazoline (5a). Similarly, several nitrogen-containing heteroarenes (4, 9, 12, 16-19) having an α-hydroxybenzyl group at the α-position of the nitrogen underwent retro-benzoin type condensation to afford kelones (2) and heteroarenes (5). However, similar reaction of pyrazolopyrimidines (13, 14, 15) having an α-benzyl-α-hydroxybelzyl group resulted in benzyl migration, giving benzylpyrazolopyrimidines (8) and arenecarbaldehydes (3). Tetrabutylammonium cyanide (11, Bu4NCN) was a more effective cyanide ion donor than KCN (10). The retro-benzoin condensation was applied to the synthesis of 2-substituted quinazolines (38) from 2-chloro-4- aroylquinazolines (34), using the aroyl group as a protecting and electron- withdrawing group.

Carbon-carbon bond cleavage of α-hydroxybenzyl-heteroarenes to ketones and heteroarenes by catalytic action of cyanide ion based on retrobenzoin condensation

Treatment of 4-(α-benzyl-α-hydroxybenzyl)quinazoline (2a) with potassium cyanide in DMF resulted in carbon-carbon bond cleavage to give benzyl phenyl ketone (3a) and quinazoline (4). Similar results were obtained with other 4-(α-hydroxybenzyl)quinazolines (2b-f and 7a). This reaction proceeds through retrobenzoin condensation. This condensation also proceeded in pyrazolopyrimidine (9a) triazolopyrimidine (10a), quinoxaline (11a), and benzimidazole (12a), and the imidazolium salt (16) was an effective catalyst.