Synthesis of the Macrolactone Cores of Maltepolides via a Diene-Ene Ring-Closing Metathesis Strategy.

Synthesis of the C19-truncated maltepolide E has been accomplished via a diene-ene ring-closing metathesis (RCM) strategy without damage to the C11-C14 alkenyl epoxy unit. Upon release of the C17-OH group, it attacked at the C14 position with double bond migration and epoxide ring opening to furnish the C19-truncated maltepolides A and B as proposed for the biosynthesis of maltepolides.

High-Efficiency Solution-Processed Organic Light-Emitting Diodes with Tetradentate Platinum(II) Emitters.

The realization of high-efficiency solution-processed organic light-emitting diodes (OLEDs) using phosphorescent tetradentate Pt(II) emitters and bipolar organic hosts is demonstrated in this work. To investigate the effect of organic host on the platinum dopant, the performances of solution-processed Pt-OLEDs with various combinations between four tetradentate Pt(II) emitters, including two newly developed and and three bipolar organic hosts , , and , have been analyzed and compared. Among the tetradentate Pt(II) complexes studied in this work, exhibited the best electroluminescent performance attributable to its bulky molecular scaffold structure, high emission quantum yield, and good solubility in common organic solvents.