Effects of electronics, aromaticity, and solvent polarity on the rate of azaquinone-methide-mediated depolymerization of aromatic carbamate oligomers.

This paper uses physical-organic studies on well-defined oligomers to establish design principles for creating aromatic poly(carbamates) that depolymerize from head-to-tail in low dielectric constant environments when exposed to specific applied signals. We show that either increasing electron density or decreasing the aromaticity of aromatic repeating units in poly(carbamates) increase the overall depolymerization rate. For example, a methoxybenzene-based repeating unit provides depolymerization rates that are 143× faster than oligomers that contain a benzene-based repeating unit.

A thermally-stable enzyme detection assay that amplifies signal autonomously in water without assistance from biological reagents.

This Communication describes a thermally-stable small molecule and a corresponding assay strategy that autonomously amplifies a colorimetric signal when a specific enzyme biomarker is detected.

A self-immolative spacer that enables tunable controlled release of phenols under neutral conditions.

A current challenge in the area of responsive materials is the design of reagents and polymers that provide controlled release of phenols in environments that are less polar than water. In these contexts, a molecular strategy that enables release of nearly any phenol with predictable and tunable rates and without complication from background hydrolysis would substantially increase the precision with which materials can be designed to respond to a particular signal. This Article addresses this problem at the fundamental level by describing the design, synthesis, and physical-organic characterization of two small molecule self-immolative spacers that are capable of releasing phenols in organic and mixed organic-aqueous solutions.

Design of small molecule reagents that enable signal amplification via an autocatalytic, base-mediated cascade elimination reaction.

This Communication describes three small molecule reagents that amplify the signal for a detection event via an autocatalytic reaction. Two signals are obtained from each reagent: (i) the dibenzofulvene chromophore and (ii) piperidine, which can be visualized using a pH indicator dye. The reagents are demonstrated in a model assay for palladium.