A highly efficient total synthesis of dictyodendrins A-E was accomplished. The synthesis features a novel benzyne-mediated one-pot indoline formation/cross-coupling sequence for the construction of a highly substituted key indoline intermediate. Peripheral substituents were introduced onto this intermediate in a modular fashion to complete the total synthesis of dictyodendrins A-E.

Our recent experimental studies on the 1/8 anomaly in the Bi-2212 and Y-123 phases and on the new anomaly at x = 0.21 in La2-xSr x Cuiy ZnyO4 are reviewed. In the Zn-substituted Bi-2212 and Y-123 phases, we have found anomalous suppression of superconductivity at p (the hole concentration per Cu in the CuCh plane)-1/8, and it has been found from the muon spin relaxation (// SR) measurements that the magnetic correlation between Cu spins is enhanced singularly at p ~ 1/8. Furthermore, we have found marked suppression of superconductivity singularly at x = 0.21 in the 1% Zn-substituted single-crystals of La2-xSr x Cuiy ZnyO4, and it has been found from the // SR measurements that the magnetic correlation is also enhanced at x = 0.21. These results suggest that the dynamical stripe correlations of holes and spins exist in the Bi-2212 and Y-123 phases as well as in the La-214 phase and that they tend to be pinned by Zn, leading to the suppression of superconductivity. If this tendency is the case in a wide range of p, it is possible to understand the universal results in the high-T c cuprates that Zn is a strong scatterer and that the Zn substitution markedly suppresses superconductivity.

In‐do‐line of fire: A highly efficient total synthesis of the title compounds features a novel benzyne‐mediated one‐pot indoline formation/cross‐coupling sequence for the construction of a highly substituted key indoline intermediate. The peripheral substituents were then introduced onto the intermediate in a modular fashion to complete the total syntheses of dictyodendrin A and B.

A benzyne-mediated synthesis of substituted indolines and carbazoles was developed. The reaction includes generation of benzyne using Mg(TMP)2·2LiCl as a base, cyclization, and trapping the resulting organomagnesium intermediate with an electrophile to provide a series of substituted indolines and carbazoles in a regiospecific manner. This was applied to a concise five-pot total synthesis of heptaphylline.

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