Substrate-dependent regiodivergence in [3 + 2] annulation reactions of 2-(phenacylethylidene)cyclobutanones with thioureas.

The [3 + 2] annulation reaction between a thiourea, an ambident dinucleophile, and a 2-(phenacylethylidene)cyclobutanone, containing a novel pull-pull alkene system, could in principle proceed with several chemo- and regioselectivity profiles. Here we describe a convenient synthesis of the functionalized cyclobutanone substrates and show that they react with thioureas in a manner that is rationalized mechanistically in terms of the steric and electronic effects at play. The [3 + 2] annulation proceeds in mild, additive-free conditions to provide access to previously unknown cyclobutane-fused imidazolidine-2-thione and thiazolidine-2-imine derivatives in good yields.

The Heyns Rearrangement: Synthetic Routes Beyond Carbohydrate Chemistry.

This concept review describes the recent achievements on the Heyns rearrangement appeared in literature over the last decade and aims to provide the reader with a general overview of the fundamental synthetic advances in this research area.

Mechanochemistry for Healthcare: Revealing the Nitroso Derivatives Genesis in the Solid State.

Nitroso derivatives with unique characteristics have been extensively studied in various fields, including biology and clinical research. Although there has been substantial investigation of "nitrosable" components in many drugs and commonly consumed nutrients, there is still a need for a higher awareness about their formation and characterization. This study demonstrates how these derivatives can be produced through a mechanochemical procedure under solid-state conditions.

Mechanochemistry Frees Thiourea Dioxide (TDO) from the 'Veils' of Solvent, Exposing All Its Reactivity.

The synthesis of nitrogen-based heterocycles has always been considered essential in developing pharmaceuticals in medicine and agriculture. This explains why various synthetic approaches have been proposed in recent decades. However performing as methods, they often imply harsh conditions or the employment of toxic solvents and dangerous reagents.

-Formylsaccharin: A Sweet(able) Formylating Agent in Mechanochemistry.

The acylation of amines has always attracted a deep interest as a synthetic route due to its high versatility in organic chemistry and biochemical processes. The purpose of this article is to present a mechanochemical acylation procedure based on the use of acyl-saccharin derivatives, namely -formylsaccharin, -acetylsaccharin, and -propionylsaccharin. This protocol furnishes a valuable solvent-free alternative to the existing processes and aims to be highly beneficial in multi-step procedures due to its rapid and user-friendly workup.

Mechanochemistry: New Tools to Navigate the Uncharted Territory of "Impossible" Reactions.

Mechanochemical transformations have made chemists enter unknown territories, forcing a different chemistry perspective. While questioning or revisiting familiar concepts belonging to solution chemistry, mechanochemistry has broken new ground, especially in the panorama of organic synthesis. Not only does it foster new "thinking outside the box", but it also has opened new reaction paths, allowing to overcome the weaknesses of traditional chemistry exactly where the use of well-established solution-based methodologies rules out progress.

A trustworthy mechanochemical route to isocyanides.

Isocyanides are hardly produced, dramatically sensitive to purification processes, and complex to handle as synthetic tools. Notwithstanding, they represent one of the most refined and valuable compounds for accessing sophisticated and elegant synthetic routes. A unique interest has always been addressed to their production, though their synthetic pathways usually involve employing strong conditions and toxic reagents.

Appealing Renewable Materials in Green Chemistry.

In just a few years, chemists have significantly changed their approach to the synthesis of organic molecules in the laboratory and industry. Researchers are encouraged to approach "greener" reagents, solvents, and methodologies, to go hand in hand with the world's environmental matter, such as water, soil, and air pollution. The employment of plant and animal derivates that are commonly regarded as "waste material" has paved the way for the development of new green strategies.

Tandem Wittig Reaction-Ring Contraction of Cyclobutanes: A Route to Functionalized Cyclopropanecarbaldehydes.

An original tandem reaction consisting of a Wittig reaction-ring contraction process between α-hydroxycyclobutanone and phosphonium ylides has been developed. Highly functionalized cyclopropanecarbaldehydes are obtained in good to high yield.