Transition Metal-Free Domino Hydroamination/Isomerization/Transamidation Sequence: An Entry to Trifluorinated γ-Lactams.

A method for the construction of trifluorinated-5-methylenepyrrolidinone is reported. This strategy combines an acid-catalyzed two-carbon homologation process between ynamides and aldehydes, providing CF-substituted dienes followed by a metal-free domino hydroamination/isomerization/transamidation sequence, delivering trifluorinated-5-methylenepyrrolidinone stereoselectively.

Evolutionary metabolomics of specialized metabolism diversification in the genus highlights acylnornicotine innovations.

Specialized metabolite (SM) diversification is a core process to plants' adaptation to diverse ecological niches. Here, we implemented a computational mass spectrometry-based metabolomics approach to exploring SM diversification in tissues of 20 species covering phylogenetics sections. To markedly increase metabolite annotation, we created a large in silico fragmentation database, comprising >1 million structures, and scripts for connecting class prediction to consensus substructures.

Synthesis of Non-natural Aza-Iridoids Ynamides and Molecular Networking-Based Tracing of Their Bioconversion.

A synthesis of new-to-nature aza-iridoids ynamides is presented. ZrCl proved to be the best acid to perform this transformation. Various ynamides were accommodated, and -iridoids could be obtained as well.

Copper-Catalyzed Synthesis of Terminal vs. Fluorine-Substituted N-Allenamides via Addition of Diazo Compounds to Terminal Ynamides.

A copper-mediated coupling reaction between ynamides and diazo-compounds to produce N-allenamides is reported for the first time. This method enables facile and rapid access to terminal N-allenamides by using commercially available TMS-diazomethane with wide functional group compatibility on the nitrogen. Furthermore, the ubiquity of molecules containing a fluorine moiety in medicine, in agricultural, and material science requires the continuous search of new building blocks, including this unique surrogate.