In 2022,Epton, Ryan G.; Unsworth, William P.; Lynam, Jason M. published an article in Organometallics. The title of the article was 《Selectivity, Speciation, and Substrate Control in the Gold-Catalyzed Coupling of Indoles and Alkynes》.SDS of cas: 78191-00-1 The author mentioned the following in the article:
A convenient and mild protocol for the Au-catalyzed intermol. coupling of substituted indoles with carbonyl-functionalized alkynes to give vinyl indoles is reported. This reaction affords 3-substituted indoles in high yield, and in contrast to the analogous reactions with simple alkynes which give bisindolemethanes, only a single indole is added to the alkyne. The protocol is robust and tolerates substitution at a range of positions of the indole and the use of ester-, amide- and ketone-substituted alkynes. The use of 3-substituted indoles as substrates results in the introduction of the vinyl substituent at the 2-position of the ring. A combined exptl. and computational mechanistic study revealed that the Au catalyst has a greater affinity to the indole than the alkyne, despite the C-C bond formation step proceeding through an η2(π)-alkyne complex, which helps to explain the Stark differences between the intra- and intermol. variants of the reaction. Also the addition of a 2nd indole to the carbonyl-containing vinyl indole products is both kinetically and thermodynamically less favored than in the case of more simple alkynes, providing an explanation for the observed selectivity. Finally, a highly unusual Au-promoted alkyne dimerization reaction to form a substituted Au pyrylium salt was identified and studied. In the experiment, the researchers used many compounds, for example, N-Methoxy-N-methylacetamide(cas: 78191-00-1SDS of cas: 78191-00-1)
N-Methoxy-N-methylacetamide(cas: 78191-00-1) belongs to anime. Nitrous acid converts secondary amines (aliphatic or aromatic) to N-nitroso compounds (nitrosamines): R2NH + HNO2 → R2N―NO. Some nitrosamines are potent cancer-inducing substances, and their possible formation is a serious consideration when nitrites, which are salts of nitrous acid, are present in foods or pharmaceutical preparations. Tertiary amines give rise to nitrosamines more slowly; an alkyl group is eliminated as an aldehyde or ketone, along with nitrous oxide, N2O.SDS of cas: 78191-00-1
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics