Nuances in Fundamental Suzuki–Miyaura Cross-Couplings Employing [Pd(PPh₃)₄]: Poor Reactivity of Aryl Iodides at Lower Temperatures

We have explored fundamental Pd-catalyzed C_sp²–C_sp² Suzuki–Miyaura cross-couplings of aryl iodides (Ar–I) employing “classical” Pd/PPh₃ catalyst systems. Surprisingly, we observed particularly inefficient couplings of these ostensibly reactive electrophiles in a range of conventional solvent mixtures at lower temperatures (∼50 °C), which was in stark contrast to analogous reactions featuring the equivalent aryl bromides. This feature of well-established Pd/PPh₃-mediated Suzuki–Miyaura reactions has received scant attention in the literature. Most significantly, our studies suggest that the inefficient coupling of aryl iodides at lower temperatures derives from the unexpectedly poor turnover of the key on-cycle intermediate <i>trans</i>-[Pd­(PPh₃)₂(Ar)­(I)] (or related Pd^II–I species) in the presence of PPh₃

Advanced inorganic chemistry laboratory curricula in Australian universities: investigating the major topics and approaches to learning

The teaching laboratory remains an important environment for developing undergraduate chemists, but the inherent diversity of inorganic chemistry results in less standardised undergraduate curricula than other sub-disciplines. This study surveys the content of advanced (third-year) inorganic chemistry across Australia and reviews experimental materials from 15 universities that offer inorganic laboratory programmes at this level. All institutions offer at least one traditional inorganic experiment, the most common being the preparation and acetylation of ferrocene, spectroscopy and magnetochemistry of nickel coordination compounds and palladium-catalysed cross-couplings. These inorganic classics are complemented by a breadth of non-traditional offerings that often align with institutional research strengths. Academic unit coordinators were also surveyed and their responses interpreted using ASELL (Advancing Science and Engineering through Laboratory Learning) tools. Advanced inorganic laboratory programmes were found to develop students' practical and transferrable skills. Students generally receive guidance from teaching staff in all aspects of experimental work, including planning, development, analysis and communicating conclusions. Academic unit coordinators identified potential improvements that included diversifying student activities in the lab and how they are being assessed

Visible light dye-photosensitised oxidation of pyrroles using a simple LED photoreactor

The photooxidation of pyrrole is typically low yielding due to the absorbance of ultraviolet light, which leads to uncontrolled polymerisation and decomposition. Presented herein is the development of a simple and cost-effective photoreactor utilising Light Emitting Diodes (LEDs) as the light source, and its application to the dye-sensitised oxidation of a range of pyrroles to give corresponding 3-pyrrolin-2-ones. The broader applicability of this approach to the generation of 1O2 is also explored

Seven-membered rings

This review covers work published in the calendar year 2014. Novel reaction chemistry and new ring synthetic methods for seven-membered heterocycles including azepines, benzoazepines, oxepines, thiepines, diazepines, benzodiazepines, dioxepines, dithiepines are reviewed

Seven-membered rings

This review covers the work published in the calendar year 2013. Novel reaction chemistry and new ring synthetic methods for azepines, benzoazepines, oxepines, thiepines, diazepines, benzodiazepines, dioxepines, and dithiepines, are reviewed