Energetic silicones: synthesis and characterization of pentaoxadiazole-PDMS copolymers.

Standing at the forefront of energetics research is the exploration of energetic binders. To avoid the traditionally used sensitive explosophores, we present the first reported energetic silicone polymers synthesized from a penta-oxadiazole monomer. These polymers exhibit properties that lie between, or exceed, the thermal properties of inert and commonly used energetic binders.

"Design of Experiments" as a Method to Optimize Dynamic Disulfide Assemblies: Cages and Functionalizable Macrocycles.

Cyclophanes are a venerable class of macrocyclic and cage compounds that often contain unusual conformations, high strain, and unusual properties. However, synthesis of complex, functional derivatives remains difficult due to low functional group tolerance, high dilution, extreme reaction conditions, and sometimes low yields using traditional stepwise synthetic methods. "Design of experiments" (DOE) is a method employed for the optimization of reaction conditions, and we showcase this approach to generate a dramatic increase in the yield of specific targets from two different self-assembling systems.

Self-Assembly of a Trithioorthoformate-Capped Cyclophane and Its Endohedral Inclusion of a Methine Group.

An unusual trithioorthoformate-capped cyclophane cage was assembled via antimony-activated iodine oxidation of thiols as confirmed by H-NMR spectroscopy and X-ray crystallography. The disulfide bridges can undergo desulfurization with hexamethylphosphorous triamide (HMPT) at ambient temperature to capture a trithioether cyclophane cage capped by the trithioorthoformate. In both cages a methine proton points directly into the small cavity.

Methanesulfonyl-polarized halogen bonding enables strong halide recognition in an arylethynyl anion receptor.

A 3,5-bis((2-iodophenyl)ethynyl)pyridinium scaffold was synthesized which introduces the use of methanesulfonyl withdrawing groups to polarize iodine halogen bonding units for anion binding. We investigate the capability of this receptor to bind halides in polar media, while further probing the structure-property relationship of this well-polarized yet under-explored halogen bonding system.