Latent Class Analysis for the Diagnosis of Clostridioides difficile Infection.

Background: Clostridioides difficile infection (CDI) is an opportunistic disease that lacks a gold-standard test. Nucleic acid amplification tests such as real-time polymerase chain reaction (PCR) demonstrate an excellent limit of detection (LOD), whereas antigenic methods are able to detect protein toxin. Latent class analysis (LCA) provides an unbiased statistical approach to resolving true disease.

Dramatic effect of Lewis acids on the rhodium-catalyzed hydroboration of olefins.

The addition of Lewis acids such as trispentafluoroboron as cocatalysts has been found to have a dramatic effect on the Rh-catalyzed hydroboration of olefins with pinacol borane. For example, aliphatic olefins do not react at all in noncoordinating solvents, but with the addition of 2% of B(C(6)F(5))(3), the reaction is complete in minutes. Similarly, the reaction of aromatic olefins with HBPin occurs slowly and nonselectively in the absence of B(C(6)F(5))(3), but is accelerated and occurs more selectively in its presence.

Expanding the scope of transformations of organoboron species: carbon-carbon bond formation with retention of configuration.

The use of boron chemistry for the synthesis of enantiomerically enriched organic compounds is described. Key advances towards the preparation of organoboranes with control of stereochemistry are supplemented by a discussion of the use of these chiral organoboranes in carbon-carbon bond forming reactions. Particular emphasis is given to advances in the Suzuki-Miyaura coupling of chiral secondary organoboranes and homologation reactions.

The synthesis and resolution of 2,2'-, 4,4'-, and 6,6'-substituted chiral biphenyl derivatives for application in the preparation of chiral materials.

Various routes were examined for the synthesis of chiral biphenyl species that are substituted at the 2,2', 4,4' and 6,6' positions. Because the biaryl bond is tetrasubstituted, many coupling reactions were not suitable. The most reliable coupling reaction proved to be the Ullmann, which gave the desired product in 82% yield.