Photo Energy Transfer-Enabled Thiosulfinylation of Alkynes for Asymmetric Synthesis of Sultims.

An asymmetric and highly practical thiosulfinylation of alkynes is established for the synthesis of sultim derivatives. The disclosed platform featured broad substrate scope and group tolerance for diverse biologically important molecules under mild and operationally simple conditions. Notably, the obtained chiral sulfinyl derivatives have demonstrated their potential application in further gram-scale synthesis and product derivatizations, providing a chance for drug discovery.

Synthesis of constrained bicycloalkanes through bibase-promoted brook rearrangement/radical-polar crossover cyclization.

Highly constrained bicyclic scaffolds are ubiquitous and attracting increasing interest in pharmaceutical and biotechnology discoveries owing to the enhanced activities. Herein, we report a protocol to access highly substituted constrained bicycloalkanes from readily accessible α-silyl alcohols and olefins through a bibase-promoted Brook rearrangement/radical-polar crossover cyclization (RPCC) process. Of note, the practical procedure features broad substrate scope and good group tolerance under mild and operationally simple conditions, using an inexpensive organic photocatalyst.

Compact Slot Microring Resonator for Sensitive and Label-Free Optical Sensing.

A novel all-pass slot microring resonator (SMRR), intended for label-free optical biosensing based on silicon-on-insulator platforms, is proposed. The sensor consists of a bent asymmetric directional coupler and an asymmetric-slot microring waveguide. The appropriate slot width of 140 nm is identified by the three-dimensional finite-difference time-domain (3D-FDTD) method for better light-matter interaction in applications.