Guidelines for the application of the Scholl reaction were developed. Labeling experiments demonstrate that the Scholl reaction fails in small, unsubstituted oligophenylenes (e.g., o-terphenyl) due to oligomerization of the products (e.g., triphenylene). Incorporation of suitably placed blocking groups (e.g., t-butyl) suppresses oligomerization. The well-established directing group effects in electrophilic aromatic substitution predict the outcome of Scholl reactions of substituted substrates. Activating o,p-directing groups (e.g., MeO) direct bond formation o,p, either intramolecularly or intermolecularly. Deactivating o,p-directing groups (e.g., Br) also direct bond formation o,p but yields are lower. Deactivating m-directors (e.g., NO2) suppress reaction. MoCl5 and PhI(OOCCF3)2/BF3.Et2O are general and effective reagents for the Scholl oxidation. Calculations (B3LYP/6-31G(d)) predict the Scholl reaction in alkoxyarenes to proceed via arenium cations, not radical cations. Suzuki-Miyaura couplings were used to generate 12 substituted o-terphenyl derivatives.

Myotonic dystrophy (DM) is one of the most common forms of muscular dystrophy. DM is an autosomal dominant disease caused by a toxic gain of function RNA. The toxic RNA is produced from expanded non-coding CTG/CCTG repeats, and these CUG/CCUG repeats sequester the Muscleblind-like (MBNL) family of RNA binding proteins. The MBNL proteins are regulators of alternative splicing, and their sequestration has been linked with mis-splicing events in DM. A previously reported screen for small molecules found that pentamidine was able to improve splicing defects associated with DM. Biochemical experiments and cell and mouse model studies of the disease indicate that pentamidine and related compounds may work through binding the CTG*CAG repeat DNA to inhibit transcription. Analysis of a series of methylene linker analogs of pentamidine revealed that heptamidine reverses splicing defects and rescues myotonia in a DM1 mouse model.

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Biphenylation using (Li(THF)(4))(2) x Zr(biphe)(3) of hexabromotriptycenes bearing H (1-H) or Bu (1-Bu) at the bridgeheads gave triptycenes with triphenylene blades. The blades extend both perpendicular and parallel to the 3-fold axis and generate a large intramolecular free volume (IMFV) (1-H, AM1, 710 A(3); cf. triptycene, AM1 71 A(3)). Crystals of 1-H could not be obtained. Triptycene 1-Bu, in which the Bu groups fill the voids near the bridgehead, was crystalline. X-ray diffraction analysis revealed crystal packing with alternating, interlocked corrugated and distorted hexagonal layers.

A synthesis is described of the four C-halogenated 1-X-CB11H11- anions (X = I, Br, Cl, F) using N-halosuccinimides and N-fluorobis(benzenesulfonyl)amine as halogenating agents. The procedure yields only the desired product next to unreacted starting material. Regularities in the 11B and 13C NMR chemical shifts of singly halogenated icosahedral carboranes are summarized.