Homologation of Ugi and Passerini reactions using ynamides

Green synthesis, crystal structure, and antifungal activities of (E)-4-arylidene-5-oxotetrahydrofuran

A series of γ-lactone derivatives (E)-4-arylidene-5-oxotetrahydrofuran derivatives were synthesized via a tandem Passerini 3CC/SN cyclization microwave-assisted one-pot method efficiently starting from Baylis Hillman acids, aryl glyoxals and isocyanides, and using ionic liquid as reaction medium. The products were characterized by hydrogen nuclear magnetic resonance spectroscopy (1H-NMR), carbon nuclear magnetic resonance spectroscopy (13C-NMR). Single crystal X-ray analysis of the compound RPDFB clearly confirmed its assigned chemical structures. Meanwhile, the effects of four compounds (RPDFB, RPDFC, RPDFI, RPDFJ) on the growth inhibition activity of Gibberella zeae were detected, and found that the compound RPDFB has significant growth inhibition activity to Gibberella zeae.

Asymmetric synthesis with ynamides: unique reaction control, chemical diversity and applications

Ynamides are among the most powerful building blocks in organic synthesis and have become invaluable starting materials for the construction of multifunctional compounds and challenging architectures that would be difficult to prepare otherwise. The rapidly growing popularity originates from the unique reactivity and ease of manipulation of the polarized ynamide triple bond, the advance of practical methods for making them, and the simplicity of storage and handling. These attractive features and the demonstration of numerous synthetic applications have spurred the development of intriguing asymmetric reaction strategies during the last decade. An impressive variety of chemo-, regio- and stereoselective carbon-carbon and carbon-heteroatom bond forming reactions with ynamides have been developed and now significantly enrich the toolbox of synthetic chemists. This review provides a comprehensive overview of asymmetric ynamide chemistry since 2010 with a focus on the general scope, current limitations, stereochemical reaction control and mechanistic aspects.