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Highly selective palladium-catalyzed of 3,6-diiodopyridazine with various primary and secondary amines including amino acid esters was carried out. Because of the simple insertion regarding both iodoarene functionalities, the corresponding 3,6-diamides were synthesized in moderate to high yields. The exclusive formation of amides, that is, the missing of 2-ketoamides which might be formed via double insertion, can be explained by the close proximity of the nitrogen of the aromatic ring to the iodo substituent. The unexpected selectivity of the is rationalized by a mechanistic approach. [ABSTRACT FROM AUTHOR]

Abstract: 1-Isoindolinone derivatives were synthesised in high yields (up to 89%) by using 2-iodobenzyl bromide and 2-iodobenzylamine as bifunctional substrates in palladium-catalysed carbonylation. Depending on the N-nucleophiles, two types of compounds were synthesised with 2-iodobenzyl bromide: the use of primary amines, including amino acid methylesters, resulted in the formation of N-substituted 1-isoindolinones, while secondary amines react both with the benzyl bromide and iodoarene moieties resulting in the corresponding ortho-(N-piperidino/morpholinomethyl)-benzamides. The parent 1-isoindolinone was obtained in a facile, highly chemoselective intramolecular aminocarbonylation of 2-iodobenzylamine. The mechanistic details of the ring-closure reaction and the conditions leading to side-products are discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: 17-Alkoxycarbonyl- and 17-carboxamido-3β-hydroxy-13α-androsta-5,16-diene derivatives were synthetized in high yields in the palladium-catalyzed carbonylation reactions of the corresponding 3β-hydroxy-17-iodo-13α-androsta-5,16-diene. This substrate with a 17-iodo-16-ene functionality was obtained from the 17-keto derivative via its 17-hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethylguanidine). 17-Carboxamides were obtained by chemoselective aminocarbonylation through the use of amines, including amino acid esters, as N-nucleophiles. The 17-methoxycarbonyl-16-ene derivative was synthetized by using methanol as O-nucleophile. The parent compound of this series, the 17-carboxylic acid derivative, was formed in the presence of water via hydroxycarbonylation. [Copyright &y& Elsevier]

Abstract: Various amine nucleophiles including glycine methyl ester were used in the palladium-catalysed aminocarbonylation of (E)- and (Z)-1-iodo-1-dodecene. The substrates were synthesised from 1-dodecanal via the corresponding hydrazone, which was treated with iodine in the presence of tetramethylguanidine. The homogeneous catalytic aminocarbonylation resulted in the corresponding odd-number carboxamides in moderate to good yields. The reaction was accompanied by the formation of some carboxamides with triple bonds in the 2-position. The latter products were formed in relatively high yields with secondary amines such as piperidine and morpholine and were isolated as pure compounds. [Copyright &y& Elsevier]

Abstract: Highly reactive iodoalkenes (α-iodostyrene and α,α′-diiodo-1,4-divinylbenzene) were prepared and used as substrates in palladium-catalysed aminocarbonylation reaction. Regardless of the type of amine nucleophile the corresponding N-substituted phenylacrylamides have been formed chemoselectively in nearly quantitative yields. High isolated yields (up to 83%) have been achieved both with unfunctionalised simple amines and amino acid methyl esters under mild reaction conditions. [Copyright &y& Elsevier]

Abstract: Various primary and secondary amines, including amino acid methyl esters, were used as nucleophiles in palladium-catalysed aminocarbonylation of 2-iodopyridine, 3-iodopyridine and iodopyrazine. N-Substituted nicotinamides and 3-pyridyl-glyoxylamides (2-oxo-carboxamide type derivatives) of potential biological importance can be obtained from 3-iodopyridine as a result of simple and double carbon monoxide insertions, respectively. The latter examples can be obtained in synthetically acceptable yields by using elevated carbon monoxide pressure. On the contrary, N-alkyl/aryl-carboxamides were obtained exclusively in the whole pressure range by using 2-iodopyridine and iodopyrazine. [Copyright &y& Elsevier]

Highlights: [•] Novel androstane-based 3,17-dicarboxamides were synthesized. [•] Systematic investigation on the synthesis of homo- and mixed diamides was carried out. [•] The products are potential 5α-reductase inhibitors of pharmacological importance. [•] High-yielding aminocarbonylation was used as key-reaction in the multistep synthesis. [Copyright &y& Elsevier]

Abstract: 1-Iodocyclohexene, a benchmark substrate, has been double carbonylated in the presence of palladium-phosphite precatalysts. Triarylphosphites with OR substituents, able to act both as P-monodentate and hemilabile P,O-heterobidentate ligands were used in this reaction. Systematic investigations have revealed that the chemoselectivity towards cyclohexenylglyoxylamides, i.e., the products obtained in aminocarbonylation by the insertion of two carbon monoxide, is strongly influenced by the amine nucleophile, temperature and carbon monoxide pressure. The highest yields of 2-ketocarboxamides were obtained at low temperature (30 °C) and high carbon monoxide pressure (110 bar). However, the structure of the phosphite ligand has practically no effect either on catalytic activity or chemoselectivity. This fact refers to the P-monodentate coordination of the ligands in catalytic intermediates or that palladium nanoparticles are the catalytically active species. [Copyright &y& Elsevier]