Silver-Mediated Oxidative Decarboxylative Intramolecular Asymmetric Radical Cyclization (Csp3-Csp2) via Memory of Chirality: Access to Circumdatin Alkaloids

Cyanomethylative cyclization of unactivated alkenes with nitriles for the synthesis of cyano-containing ring-fused quinazolin-4(3H)-ones

The synthesis of cyano-containing pyrrolo- and piperidino-quinazolinones was developed using alkyl nitriles through radical cascade addition/cyclization under metal-free conditions.

Peroxide-Mediated Oxidative Radical Cyclization to the Quinazolinone System: Efficient Syntheses of Deoxyvasicinone, Mackinazolinone and (±)-Leucomidine C

An efficient protocol for obtaining fused quinazolinones through an oxidative free-radical cyclization under metal- and tin-free conditions is described. The oxidative cyclization of various N-3-ω-iodoalkyl derivatives to provide tricyclic systems using dicumyl peroxide as the sole reagent is studied. The method then is employed for the syntheses of 5-, 6-, and 7-membered fused quinazolinone analogues, including the natural products deoxyvasicinone and mackinazolinone. A xanthate-based oxidative radical cascade addition/cyclization process that allows the production of new menthol- and testosterone-quinazolinone conjugates, as well as the first total synthesis of leucomidine C, are also reported.

Construction of novel bridged aromatic ring-fused oxazocine frameworks via an N-heterocyclic carbene-catalyzed azabenzoin reaction and radical-initiated cascade cyclization

A novel method for the construction of 1,5-methanobenzo[f][1,3]oxazocin-6-ones and 6,10-methanopyrido[3,2-f][1,3]oxazocin-5-ones from o-vinyl aromatic aldehydes and N-acylarylimines was developed via NHC-catalyzed and radical-initiated reactions.

Carboalumination of Seven-Membered-Ring trans-Alkenes

Seven-membered-ring trans-alkenes undergo rapid hydro- and carboalumination reactions in the absence of a catalyst with complete regio- and diastereoselectivity. Control experiments, including deuterium labeling, adding radical inhibitors, and using a radical clock, suggest that these reactions proceed by a concerted mechanism. The products of the reaction possess a new carbon-aluminum bond that can then undergo subsequent transformations, particularly oxidation, providing functionalized products as single stereoisomers.

C–H functionalization of quinazolinones by transition metal catalysis

Quinazolinone and its derivatives are an important class of heterocyclic scaffolds in pharmaceuticals and natural products. This review provides the recent research advances in the transition metal catalyzed selective C–H bond functionalization of quinazolinone.

Memory of Chirality as a Prominent Pathway for the Synthesis of Natural Products through Chiral Intermediates

The ability of a chiral molecule to be able to transform from one structure to another, whilst remembering its original molecular information by means of an appropriate transition state is an abstract notion that may very well play a key role in important synthetic processes, and has thus attracted a considerable amount of attention among the chemistry community. Here, we have highlighted this concept of "memory of chirality" (MOC) and extended it beyond the case of a simple molecule to larger and more complex natural products. Updated approaches that have recently been elucidated to obtain these asymmetric natural products are described, some of which may, until now, have been overcomplicated or overlooked.

Reductive cyclisations of amidines involving aminal radicals

The first general study of aminal radical cyclisations, triggered by reduction of amidines with SmI₂, delivers quinazolinones with complete diastereocontrol.