A fluorescent polymer of 2-naphthol is prepared using the oxidative enzyme horseradish peroxidase encapsulated in the microstructured system of AOT/isooctane reversed micelles. The monomer, being amphiphilic, partitions to the oil−water interface with the hydroxyl moieties directed toward the microaqueous core. The enzyme is encapsulated in the water core. The precipitated polymer of naphthol has the morphology of single and interconnected microspheres and is soluble in a range of polar and nonpolar organic solvents. Poly(2-naphthol) shows a fluorescence characteristic of the naphthol chromophore and an additional well-resolved fluorescence attributed to an extended quinonoid structure attached to the polymer backbone. Further evidence of the quinonoid structure is obtained through UV, IR, and NMR spectroscopy. Characteristics of the synthesis and structure of poly(2-naphthol) are compared with those of a less fluorescent polymer, poly(4-ethylphenol).

We have synthesized linear ABC triblock terpolymers containing poly(1,3-cyclohexadiene), PCHD, as an end block and characterized their morphologies in the melt. Specifically, we have studied terpolymers containing polystyrene (PS), polybutadiene (PB), and polyisoprene (PI) as the other blocks. Systematically varying the ratio of 1,2- /1,4-microstructures of poly(1,3-cyclohexadiene), we have studied the effects of conformational asymmetry among the three blocks on the morphologies using transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and self-consistent field theory (SCFT) performed with PolySwift++. Our work reveals that the triblock terpolymer melts containing a high percentage of 1,2-microstructures in the PCHD block are disordered at 110 °C for all the samples, independent of sequence and volume fraction of the blocks. In contrast, the triblock terpolymer melts containing a high percentage of 1,4-microstructure form regular morphologies known from the literature. The accuracy of the SCFT calculations depends on calculating the χ parameters that quantify the repulsive interactions between different monomers. Simulations using χ values obtained from solubility parameters and group contribution methods are unable to reproduce the morphologies as seen in the experiments. However, SCFT calculations accounting for the enhancement of the χ parameter with an increase in the conformational asymmetry lead to an excellent agreement between theory and experiments. These results highlight the importance of conformational asymmetry in tuning the χ parameter and, in turn, morphologies in block copolymers.

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A general protocol for visible‐light‐induced cyclopropanation of alkenes was developed with bromomethyl silicate as a methylene transfer reagent, offering a robust tool for accessing highly valuable cyclopropanes. In addition to α‐aryl or methyl‐substituted Michael acceptors and styrene derivatives, the unactivated 1,1‐dialkyl ethylenes were also shown to be viable substrates. Apart from realizing the cyclopropanation of terminal alkenes, the methyl transfer reaction has been further demonstrated to be amenable to the internal olefins. The photocatalytic cyclopropanation of 1,3‐bis(1‐arylethenyl)benzenes was also achieved, giving polycyclopropane derivatives in excellent yields. With late‐stage cyclopropanation as the key strategy, the synthetic utility of this transformation was also demonstrated by the total synthesis of LG100268.