A New Preparation of Optically Active N-Acyloxazolidinones via Ruthenium-Catalyzed Enantioselective Hydrogenation

Phosphine-catalyzed fixation of CO2 with γ-hydroxyl alkynone under ambient temperature and pressure: kinetic resolution and further conversion

Phosphine-catalyzed fixation of CO₂ with γ-hydroxyl alkynone under ambient temperature and pressure was achieved and the first example of chiral phosphine catalyzed kinetic resolution of propargyl alcohols via carbon dioxide fixation was demonstrated.

Advances in the use of CO2 as a renewable feedstock for the synthesis of polymers

Carbon dioxide offers an accessible, cheap and renewable carbon feedstock for synthesis. Current interest in the area of carbon dioxide valorisation aims at new, emerging technologies that are able to provide new opportunities to turn a waste into value. Polymers are among the most widely produced chemicals in the world greatly affecting the quality of life. However, there are growing concerns about the lack of reuse of the majority of the consumer plastics and their after-life disposal resulting in an increasing demand for sustainable alternatives. New monomers and polymers that can address these issues are therefore warranted, and merging polymer synthesis with the recycling of carbon dioxide offers a tangible route to transition towards a circular economy. Here, an overview of the most relevant and recent approaches to CO2-based monomers and polymers are highlighted with particular emphasis on the transformation routes used and their involved manifolds.

Direct Preparation of N-(Alk-1-en-1-yl)carbamates from Cyclic Ketones and Unsubstituted Carbamates

N-(Alk-1-en-1-yl)carbamates bearing an endocyclic carbon-carbon double bond have been prepared by the reaction of unsubstituted carbamates with tetrahydronaphthalen-2-one and chroman-2-one derivatives in the presence of a catalytic amount of 4-methylbenzene-1-sulfonic acid.

Practical modifications and applications of the sharpless asymmetric aminohydroxylation in the one-pot preparation of chiral oxazolidin-2-ones

[reaction: see text] Chiral oxazolidin-2-ones are synthetically valuable as chiral auxiliaries, and many have pharmaceutically interesting biological activity. This communication focuses on a convenient, practical one-pot preparation of chiral 4,5-disubstituted oxazolidan-2-ones in good yield with high enantioselectivities, using a modified Sharpless asymmetric aminohydroxylation of beta-substituted styrene derivatives followed by base-mediated ring closure. This procedure has been demonstrated on both small and large scale, utilizing 1, 3-dichloro-5,5-dimethyl hydantoin as an easily handled, commercially available substitute for tert-butyl hypochlorite.