Hydroamination and carboxylative cyclization reactions catalyzed by of gold(I) compounds with 1,1 '-bis(phosphino)metallocene ligands

The catalytic activity of [Au-2(mu-Cl)(mu-bis(phosphino)ferrocene)][BArF24] (BArF24 = tetrakis(bis(3,5-triflouromethyl)phenyl)borate) compounds was investigated for intermolecular hydroamination reactions and a carboxylative cyclization reaction. Two types of intermolecular hydroamination reactions were studied, the first being the hydroamination of 2-ethynylpyridine with aniline derivatives. Various [Au-2(mu-Cl)(mu-bis(phosphino)fertocene)][BArF24] compounds were successful in catalyzing this reaction, but gave low yields of the desired products. The second type of hydroamination reaction studied was the reaction of phenylacetylene with alkyl amines, including tert-butylamine, 1-hexylamine, isopropylamine, and cyclohexylamine. While the hydroamination reactions tended to give low yields, the choice of the bis(phosphino)ferrocene ligand did have an impact on the activity of the catalyst. The catalytic activity of these [Au-2(A-Cl)(mu-bis(phosphino)ferrocene)][BArF24] compounds was also studied in the carboxylative cyclization of N-benzyl-but-2-yn-1-amine. The majority of the gold catalysts examined successfully fixed carbon dioxide to this amine. The effect of changing the bis(phosphino)ferrocene ligands on the catalytic activity of these compounds will be presented for each of these catalytic systems. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

The catalytic activity of [Au-2(mu-Cl)(mu-bis(phosphino)ferrocene)][BArF24] compounds was investigated for intermolecular hydroamination reactions and a carboxylative cyclization reaction, showing that the choice of the bis(phosphino)ferrocene ligand impacted the activity of the catalyst.