Carbene-Catalyzed [3 + 3] Annulation of Enals and Vinyl Sulfoxonium Ylides.

Carbene-catalyzed [3 + 3] annulation of enals and vinyl sulfoxonium ylides has been demonstrated. This method efficiently synthesizes a range of 2-sulfenylidene-3-cyclohexen-1-ones with high atom economy. Notably, the presence of the sulfoxonium ylide moiety in the obtained products significantly enhances their potential for further synthetic transformations.

Direct Access to 3,4,6-Trisubstituted 2-Pyrones via Carbene Catalysis.

An -heterocyclic carbene-catalyzed [4 + 2] annulation of β,γ-unsaturated α-keto esters and phenylacetate esters was developed for the direct and efficient construction of 2-pyrones. This approach provides a practical synthesis pathway for various 3,4,6-trisubstituted 2-pyrones in moderate to good yields and features broad substrate scope and good functional group tolerance. Moreover, the products can also be readily transformed to naphthalene and acylamide.

Computer-aided automatic planning and biomechanical analysis of a novel arc screw for pelvic fracture internal fixation.

Background And Objective: The sacroiliac joint screw is a common fixation method for pelvic posterior ring fractures. The complex anatomical structure around the pelvis makes it impossible to find a suitable fixed path, which increases the difficulty of surgical operation. In this paper, we propose an automatic planning algorithm based on a computer-aided internal arc fixation channel for pelvic fractures for the first time.