9-Phenylfluorene: a powerful labeling agent

Straightforward and Efficient Deuteration of Terminal Alkynes with Copper Catalysis

The mild and effective preparation of deuterated organic molecules is an active area of research due to their important applications. Herein, we report an air-stable and easy to access copper(I) complex as catalyst for the deuteration of mono-substituted alkynes. Reactions were carried out in technical solvents and in the presence of air, to obtain excellent deuterium incorporation in a range of functionalised alkynes.

Enhanced Efficiency of Exciplex Emission from a 9-Phenylfluorene Derivative

The exciplex-thermally activated delayed fluorescence (exciplex-TADF) system is an excellent candidate for the fabrication of high-efficiency organic light-emitting diodes (OLEDs) because of its more easily achieved small singlet-triplet energy splitting (ΔE_ST) and doping control. However, exciplex-TADF is still faced with the problems of low external quantum efficiency (η_ext) and unclear effect of structure modification in electron acceptors. Herein, we provide a steric hindrance increase strategy to obtain high-efficiency exciplex emissions. Through introducing a 9-phenylfluorene group into N-ethylcarbazole of the dicyano-substituted 9-phenylfluorene, an electron acceptor material with increased steric hindrance is obtained, which helps the exciplex harvest a larger driving force and higher emission efficiencies. Encouragingly, the obtained OLED displays a maximum η_ext of 25.8%, which is one of the best efficiency values among reported exciplex-OLEDs, simultaneously possessing excellent current efficiency of 83.6 cd A^-1 and power efficiency of 93.7 lm W^-1. It is expected that this work will offer a new avenue for designing electron acceptors for highly efficient exciplex emissions.

The ruthenium-catalysed selective synthesis of mono-deuterated terminal alkynes

A highly efficient catalytic system is reported for chemoselective synthesis of mono-deuterated terminal alkynes using deuterium oxide in which the reaction proceeds via Ru–acetylide intermediates formed by selective activation of the sp-CH bond.

Mild deuteration method of terminal alkynes in heavy water using reusable basic resin

The mild and efficient deuteration method of terminal alkynes using a reusable anion exchange resin in D₂O has been developed.

Mild reaction conditions for the terminal deuteration of alkynes

Routinely employed syntheses of terminally deuterated alkynes often utilize strong bases (i.e., LDA, n-BuLi, or Grignard reagents) or low (i.e., -78 °C) or elevated (i.e., 56 °C) reaction temperatures; furthermore many of these procedures afford average yields and in some cases less than optimum deuterium incorporation. Herein we report the application of alternative extremely mild reaction conditions that readily afford quantitative yields of terminally deuterated alkynes in a matter of minutes with exceptional isotope incorporation at ambient temperature.