Pd-catalyzed oxidative amination of 2-alkenylquinazolin-4(3)-ones: synthesis of methylene and vinyl derivatives of pyrrolo(pyrido)[2,1-]quinazolinones.

When treated with the catalytic system Pd(OAc)/PPh/CsCO/benzoquinone in dioxane or Pd(PPh)Cl/-BuONa/CsCO/benzoquinone in toluene, 2-butenylquinazolin-4(3)-ones undergo intramolecular aza-Wacker cyclization to give methylene-substituted pyrrolo(pyrido)[2,1-]quinazolinones. The latter catalytic system is also efficient in the reaction of pentenyl(hexenyl)quinazolin-4(3)-ones but, in these cases, the aminopalladation of C-H multiple bonds significantly competed with allylic C(sp)-H bond activation which leads to hitherto unknown vinyl-substituted pyrrolo(pyrido)[2,1-]quinazolinones.

Di-, tetra-, and perhydropyrrolo[1,2-]imidazoles: The Methods of Synthesis and Some Aspects of Application.

The review summarizes and systematizes the literature data on the synthesis and some aspects of application of pyrrolo[1,2-]imidazoles. Synthetic approaches are grouped according to the degree of saturation of the product pyrroloimidazole ring. The bibliography of the review includes 110 sources over the last 15 years.

The PIFA-initiated oxidative cyclization of 2-(3-butenyl)quinazolin-4(3)-ones - an efficient approach to 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-]quinazolin-5(1)-ones.

A regioselective method for the synthesis of 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-]quinazolin-5(1)-ones - close structural analogs of naturally occurring vasicinone alkaloids - is described. The procedure is based on PIFA-initiated oxidative 5- cyclization of 2-(3-butenyl)quinazolin-4(3)-ones, in turn prepared by thermal cyclocondensation of the corresponding 2-(pent-4-enamido)benzamides. The products obtained have a good natural product likeness (NPL) score and therefore can be useful for the design of natural product-like compound libraries.

Chan-Evans-Lam 1-(het)arylation and 1-alkеnylation of 4-fluoroalkylpyrimidin-2(1)-ones.

The Chan-Evans-Lam reaction of 1-unsubstituted 4-fluoroalkylpyrimidin-2(1)-ones with arylboronic acids is reported as a facile synthetic route to hitherto unavailable 1-(het)aryl and 1-alkenyl derivatives of the corresponding pyrimidines. An efficient C-N bond-forming process is also observed by using boronic acid pinacol esters as coupling partners in the presence of Cu(II) acetate and boric acid. The 4-fluoroalkyl group on the pyrimidine ring significantly assists in the formation of the target 1-substituted products, in contrast to the 4-methyl and 4-unsubstituted substrates which do not undergo 1-arylation under similar reaction conditions.

Regioselective decarboxylative addition of malonic acid and its mono(thio)esters to 4-trifluoromethylpyrimidin-2(1)-ones.

Due to the high reactivity towards various C-nucleophiles, trifluoromethylketimines are known to be useful reagents for the synthesis of α-trifluoromethylated amine derivatives. However, decarboxylative reactions with malonic acid and its mono(thio)esters have been poorly investigated so far despite the potential to become a convenient route to β-trifluoromethyl-β-amino acid derivatives and to their partially saturated heterocyclic analogues. In this paper we show that 4-trifluoromethylpyrimidin-2(1)-ones, unique heterocyclic ketimines, react with malonic acid under organic base catalysis to regioselectively provide either Michael- or Mannich-type decarboxylative addition products depending on solvent polarity.