Highly Selective and Efficient Ring Hydroxylation of Alkylbenzenes with Hydrogen Peroxide and an Osmium(VI) Nitrido Catalyst

The Os^VI nitrido complex, Os^VI(N)(quin)₂(OTs) ( 1 , quin=2‐quinaldinate, OTs=tosylate), is a highly selective and efficient catalyst for the ring hydroxylation of alkylbenzenes with H₂O₂ at room temperature. Oxidation of various alkylbenzenes occurs with ring/chain oxidation ratios ranging from 96.7/3.3 to 99.9/0.1, and total product yields from 93 % to 98 %. Moreover, turnover numbers up to 6360, 5670, and 3880 can be achieved for the oxidation of p‐xylene, ethylbenzene, and mesitylene, respectively. Density functional theory calculations suggest that the active intermediate is an Os^VIII nitrido oxo species.     

Hydrogen Peroxide Insular Dodecameric and Pentameric Clusters in Peroxosolvate Structures

Peroxosolvates of 2‐aminonicotinic acid ( I ) and lidocaine N ‐oxide ( II ) including the largest insular hydrogen peroxide clusters were isolated and their crystal structures were determined by single‐crystal X‐ray diffraction. An unprecedented dodecameric hydrogen peroxide insular cluster was found in I . An unusual cross‐like pentameric cluster was observed in the structure of II . The topology of the (H₂O₂)₁₂ assembly was never observed for small‐molecule clusters. In I and II new double and triple cross‐orientational disorders of H₂O₂ were found. Cluster II is the first example of a peroxosolvate crystal structure containing H₂O₂ molecules with a homoleptic hydrogen peroxide environment. In II , a hydrogen bond between an H₂O₂ molecule and a peptide group ‐CONH⋅⋅⋅O₂H₂ was observed for the first time.     

Translating Molecular Recognition into a Pressure Signal to enable Rapid,Sensitive, and Portable Biomedical Analysis

Herein, we demonstrate that a very familiar, yet underutilized, physical parameter—gas pressure—can serve as signal readout for highly sensitive bioanalysis. Integration of a catalyzed gas‐generation reaction with a molecular recognition component leads to significant pressure changes, which can be measured with high sensitivity using a low‐cost and portable pressure meter. This new signaling strategy opens up a new way for simple, portable, yet highly sensitive biomedical analysis in a variety of settings.