Biobased, elastomeric polymer poly(glycerol succinate- co -maleate) (PGSMA) was produced using a “green” synthesis with added cellulose nanocrystals (CNCs) to create a novel PGSMA–CNC material. PGSMA–CNC was synthesized with the aim of developing a new strategy for successfully dispersing CNCs within a poly(lactic acid) (PLA) matrix for optimal reinforcement of tensile strength and modulus while having the added benefit of the proven toughness enhancements of PLA/PGSMA blends. Optical microscopy and fractionation in tetrahydrofuran showed that CNCs agglomerated during PGSMA–CNC synthesis and remained in agglomerates during PLA/PGSMA–CNC reactive blending. Fourier transform infrared, differential scanning calorimetry, and dynamic mechanical analyses also showed that PGSMA–CNC inhibited the formation of PGSMA crosslinks and PLA- g -PGSMA during reactive blending. These two effects resulted in loss of impact strength and only a 4% increase in tensile modulus over PLA/PGSMA at the highest CNC content. Further work in preventing CNC aggregation could help improve mechanical properties of the final blend.

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The novel intramolecular ring opening of oxabenzonorbornadienes with C1-tethered aryl halides was investigated using palladium catalysts to form fused tetracyclic frameworks. The reaction was generally found to synthesize 1,2-dihydronaphthalen-1-ol products with mild selectivity but was capable of synthesizing dehydrated naphthalene products in excellent yield and selectivity. Substituent effects on oxabenzonorbornadiene and on the iodoarene were explored along with the effects of varying tether length, where an efficient reaction was observed in nearly all cases. A total of 16 examples are reported with yields ranging from 0 to 96%.

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An improved method of the recently reported novel transition metal‐catalyzed intramolecular ring‐opening reaction of oxabenzonorbornadienes with C1‐tethered aryl halides is described. Using a nickel catalyst, fused tetracycles containing a 1,2‐dihydronaphthalen‐1‐ol framework were generated with good to excellent yields and selectivities in most cases: a result seldom obtained using the previous palladium‐catalyzed conditions. Electron‐withdrawing, electron‐donating, and bulky substituents were generally found to be well tolerated in the reaction while extension of the tether led to decreased yields.