Open Science Conversations: An Interview With Rebecca Melen, Cardiff University

As part of an ongoing series here on ACS Axial, we’re interviewing authors and librarians from around the world to find out more about their research, their published work, and the impact that open science is having on a changing landscape of research communication. This time, we talked to Prof. Rebecca Melen, Professor of Inorganic Chemistry at Cardiff University.

What can you tell me about your group's current research focus?

We're interested in homogeneous catalysis, particularly catalysis using Group13/15 elements—metal-free catalysis. At the moment, our main focus is on an area known as frustrated radical pair chemistry. This derives from the chemistry of frustrated Lewis pairs, which are systems which include a Lewis acid and a Lewis base, and generally, because of steric hindrance, they can't form an adduct. What this means is that a vacant orbital is present on the Lewis acid, and a lone pair is present on the Lewis base, and you can use these for small molecule activation. This enables reactivity typically observed in transition metal catalysis such as the reversible activation of dihydrogen, CO₂, unsaturated systems.

Until recently, almost all of the mechanisms with frustrated Lewis pairs were based upon two electron processes—but we've recently found out that in some cases, you can get single electron transfer from the Lewis base to the Lewis acid, and this generates a frustrated radical pair. We've been looking at using these in synthesis, and trying to see what reactivity we can do with these systems—perhaps we can get complementary reactivity to transition metals.

How would you describe the work in your paper, "Site-Selective C_sp³–C_sp/C_sp³–C_sp² Cross-Coupling Reactions Using Frustrated Lewis Pairs"?

Prior to our work, people had observed the radical behavior with frustrated Lewis pairs that I mentioned earlier: observing single electron transfer from the Lewis base to the Lewis acid to give you these radical species. In this study, we showed that we can generate radicals and potentially use these in synthesis—we observed, perhaps by accident, that when we take a certain Lewis acid and a Lewis base in the presence of a substrate, then we generate radicals, and we could see these radicals by EPR. This led us to wonder if we could use these radicals in synthesis, rather than just generating them.

In this paper, we showed that we could enable carbon–carbon bond formation using these frustrated Lewis pair/frustrated radical pair systems. We did lots of mechanistic studies to work out whether this was going by a two-electron pathway or a single electron pathway, and we found that in most cases, although we're generating the radicals, it's going via a two-electron pathway but for certain substrates we could potentially be observing a single electron pathway.

This mode of reactivity opens up new opportunities for selective, metal-free synthesis and could broaden the types of bond activations accessible through main-group element systems. Indeed, there have been several high impact papers published by other groups following this study.

What kind of impact do you think it's had?

Overall, the impact has been very positive. Beyond advancing the field of metal-free synthesis, it has also been important for my career. When the article was published, I was at a transitional stage between early and mid-career, and it became my first high-impact paper in the field. The recognition it brought helped establish my presence in the community and directly influenced the direction of the research my group is pursuing today.

This was published in the Journal of the American Chemical Society (JACS)—how would you describe the experience?

This was my first time as corresponding author publishing in JACS. I thought the process was very rigorous, but it was a rewarding experience. The peer review was very thorough, and it took quite a long time to address all the comments, but the feedback was constructive and ultimately improved the final published paper. The editorial team was very professional and responsive. The visibility that came with publishing in JACS allowed our work reach a broad audience, and was really good for my subsequent research and my career.

The article was published open access under your institution’s agreement with ACS—how did you discover this was available?

I found out about the open access (OA) option through my University’s open access team and our School research office, who provide clear guidance on publishing routes and institutional agreements. Cardiff has a strong commitment to supporting open access to maximise the visibility and impact of its research.

As well as the agreement between the university and ACS, which meant we could publish OA, our funders—the UK Research Council—mandate that our work has to be made OA, so there was that expectation too. Another reason is that in the UK we have the Research Excellence Framework (REF). If you have research outputs that you want to submit for inclusion in the REF, then you have to comply with their OA requirements as well.

What are your thoughts on the concept of open access?

I strongly support OA and think it's a really good idea. I think it's only right to make sure that your research is available to everybody, regardless of their institution or the resources that they have. Some institutions perhaps are less wealthy, or if you're an early career researcher who doesn't have funding, then OA makes that work available to them.

If you get funding from the public sector then you're doing your work with taxpayers' money, so it's only right to make sure they can access it. The average taxpayer probably doesn't really know what to do with the data or the findings, but if they're paying for it then there's a kind of moral obligation that they should have access to it too.

What are your thoughts on open science workflows (e.g. preprints, open data, transparent peer review) more generally?

I think they're all a really good idea, and in terms of the evolution of how we conduct and share research, they're a logical next step. I've personally not posted preprints myself—apart from one article where some of my co-authors took care of it, and I found that a really good experience for getting feedback before we submitted the paper to a journal. It's something I should do more of, but I haven't gotten around to it yet.

Open data is something we do, again, because of our funders—we have to link to all the raw data in our papers, and make that data publicly available. While I think this is a very good idea, the problem with this is that there is little guidelines regarding the quality of that data and how it is presented. For us it's often a massive amount of raw NMR data or X-ray data; unless it's easy to navigate and find what you're looking for, then I'd rather just go straight to the paper's supplementary information and look at the experimental data or the NMR spectra.

I'm a strong supporter of transparent peer review. I think it's very good to ensure the rigor of the process and make it more transparent, and it's also a good learning experience for early career researchers or people that are new to reviewing to see what other reviewers say.

What do you think are the biggest recent developments in open science and open access?

Probably preprints. I think that's a really good development, because sometimes the review process can take quite a long time after you've submitted a paper. Posting a preprint means that you're getting your work out there earlier.

One other major development has been the rise of institutional and funder mandates for open access publications and data, which is driving real change in publication models. I think these are both really positive movements. Perhaps one of the challenges is the cost of making research open. I hope this will come down over time, so that more people can afford to make their findings OA—but with more funders requiring OA, it's becoming more and more popular. I think 'open' will become the standard in the future—maybe in ten years' time it will be the default. I also expect, or would like to see, further innovation in how research impact is measured beyond traditional citations perhaps incorporating open metrics and public engagement.

What do you think you'd be doing if you weren't a researcher?

Before I chose to study chemistry, I wanted to be a vet. I eventually decided that I preferred doing pure science and research, but I have a couple of horses which I look after in my spare time. If I wasn't doing research, I think I'd like to do something outdoors or with animals.