Laboratory of Medicinal and Technological Chemistry, Institute of Chemistry (IQ-UnB), Campus Universitário Darcy Ribeiro, University of Brasília, Brasília 70910-900, DF, Brazil.
Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife 50670-901, PE, Brazil.
Molecules. 2022 Nov 4;27(21):7552. doi: 10.3390/molecules27217552.
We discuss herein the problems associated with using melting points to characterize multicomponent reactions' (MCRs) products and intermediates. Although surprising, it is not rare to find articles in which these MCRs final adducts (or their intermediates) are characterized solely by comparing melting points with those available from other reports. A brief survey among specialized articles highlights serious and obvious problems with this practice since, for instance, cases are found in which as many as 25 quite contrasting melting points have been attributed to the very same MCR adduct. Indeed, it seems logical to assume that the inherent non-confirmatory nature of melting points could be vastly misleading as a protocol for structural confirmation, but still many publications (also in the Q1 and Q2 quartiles) insist on using it. This procedure contradicts best practices in organic synthesis, and articles fraught with limitations and misleading conclusions have been published in the MCRs field. The drawbacks inherent to this practice are indeed serious and have misguided MCRs advances. We therefore suggest some precautions aimed at avoiding future confusions.
本文讨论了使用熔点来描述多组分反应（MCRs）产物和中间体所带来的问题。尽管令人惊讶，但仍不乏仅通过与其他报道中可用的熔点进行比较来表征这些 MCRs 最终加合物（或其中间体）的文章。在专业文章中的简要调查突出了这种做法存在严重且明显的问题，因为例如，在多达 25 种截然不同的熔点被归因于同一个 MCR 加合物的情况下。事实上，熔点作为结构确认的协议可能会产生极大误导，这似乎是合乎逻辑的假设，但仍有许多出版物（甚至在 Q1 和 Q2 区）坚持使用它。该程序违反了有机合成的最佳实践，并且在 MCRs 领域已经发表了存在局限性和误导性结论的文章。这种做法固有的缺点确实很严重，并且误导了 MCRs 的发展。因此，我们建议采取一些预防措施，以避免未来的混淆。
