Iodine‐Mediated Oxidative Annulation by C–C Cleavage: A Domino Synthetic Approach to Quinazolinones and Benzo[4,5]imidazo[1,2‐c]quinazolines

Abstract

A facile iodine-mediated unprecedented C-C cleavage by employing CuI has been established towards the synthesis of quinazolin-4(3H)-ones and benzo [4,5]imidazo[1,2-c]quinazolines. This protocol involves peroxide free synthetic approach for the stable C-C bond cleavage followed by oxidative annulation to develop a library of fused N-heterocyclic molecules.

Iodine and DMSO as Surrogate of Hazardous Metal and Non‐Metal Reagents in Organic Synthesis

“…Donthiboina and co‐workers have achieved this task via C−C bond cleavage of acetylene employing 2‐amino‐ N ‐phenylbenzamide derivatives in the presence of 1.5 equivalent of iodine and DMSO acting as solvent. The yield of desired product was escalated to 80 %, when CuI was added as a catalyst (Scheme 74 (h)) [753] …”

“…The yield of desired product was escalated to 80 %, when CuI was added as a catalyst (Scheme 74 (h)). [753] Similar to the aforementioned scaffold, the benzothiadiazine 1, 1-dioxide is another privileged moiety in all manners. [754,755] Some of the synthetic routes for benzothiadiazine, involve the use of metal catalysts such as copper (Scheme 75 (a) and (b)).…”

I2/DMSO-mediated oxidative C–C and C–heteroatom bond formation: a sustainable approach to chemical synthesis

“…44 Furthermore, it provides the advantage of the selective oxidation of alcohol to carbonyl or carboxylic acid. However, the application of H 2 O 2 as an external oxidant reduces the amount of I 2 reconverting iodide, whereas the addition of TBHP (tert-butyl hydroperoxide) to I 2 /DMSO provides opportunities to obtain various signicant compounds such as benzimidazo [1,2-c]quinazolines [45][46][47] and amidation. 7,48 In general, the reaction mechanism of I 2 /DMSO is straightforward and unambiguous.…”

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

“…Quinazolinones are hetero- cyclics represented as quinazoline ring with a keto group. Figure 12 depicts quinazolinones demonstrating various pharmacological properties like anticancer (152), antihypertensive (153) and anti-inflammatory (154) [135,136]. Many quinazolinone ring-containing alkaloids have been widely used in drug discovery and development protocols (155 and 156) [137].…”