Group work challenges each individual to employ a multitude of skills, some of which are specific to this type of task and others which the individual may never have exploited before. It commands all members to work in harmony to show good time management and a higher level of planning, and this sets it apart from individual work.
In this particular project, tasks included assessment of industrial synthesis of (S)-1-indanol and suggestions for a more green and sustainable process.
The group spent a substantial amount of time outside of the timetabled workshops, proposing ideas and examining literature sources. This report gives a personal review of the group work and research processes, including content that was not included in previous submissions and an explanation of the benefits and suggested improvements for the project.
– Part 1 – Groupwork:
Personally, I found that group work brought with it challenges I have not previously faced and simultaneously gave me an opportunity to add to my academic and practical skillsets.
Since I will be seeking an industrial placement starting in summer 2020 as part of my undergraduate degree, I have constantly been developing my CV and I am currently applying for summer internship opportunities. Even in the short space of time we have been undergoing the group work, I have found the need utilise communicative, teamwork and leadership skills – real buzzwords when it comes to applying for internships, placements and answering interview questions.
Although thus far I have been unsuccessful in my applications, I firmly believe that as a direct result of this project, I can convey to an employer that I have gained a number of attributes.
I have proved that I can listen to the suggestions of others and present ideas of my own, without being disrespectful or undermining the work of another group member. I have also shown that I can present problems associated with new synthesis ideas and demonstrate practical solutions to difficulties others have seen arising. I decided I would be the sole composer of the introduction and conclusion for our final group task, showing an ability to use technical writing to present scientific findings on behalf of a team. Finally, I hope the group presentations will give a platform to invoke the skill of being able to formally speak to a group of peers, with regards to our findings.
Despite the skills obtained, there were several difficulties associated with group-based work. Being a member who attended all workshops, most classes and all bar one group meeting, I had a first-hand experience of the difficulty in obtaining a time which suited all members to meet collectively. Additionally, finding a way for all members to have access to our group documents and reading material proved initially difficult, and one member was particularly hard to communicate with when it came to the submission of tasks.
Compromises were made, and these problems mainly overcome by forming a WhatsApp group chat and a shared resource (mega.nz cloud storage), and group meetings were scheduled by booking a room in the McClay Library on a weekly basis. Working together in a team and overcoming the associated problems is a skill which will undoubtedly be called upon in future modules and is a big part of many, if not all, graduate workplace environments.
In terms of the overall format for the group work, there were aspects which I particularly liked and some which I think could be altered for future undergraduates. I was relieved that the groups were randomly generated and not formed by the class – some people suggested that they work better in a team of people they know. However, I think random generation gave us a more realistic job of working in a team of people we didn’t previously know and prevented people from becoming comfortable or not working for the benefit of the team. Additionally, I enjoyed the benefit of being able to converse with an esteemed member of staff with regards to an active industrial problem. The workshop format allowed for an hour of this each week and even when our project leader couldn’t attend a workshop, they scheduled an alternative meeting to discuss any problems or queries.
There is only one suggested improvement for the project that springs to mind for me, that is, I would have preferred the individual report to have been due after all other tasks (including presentations). I think this would have provided more time for reflection on the whole process objectives and ultimately, a better understanding of the newly proposed synthesis. Overall, I firmly believe this project has provided a multitude of skills and experience, equipping us all for future endeavours.
– Part 2 – Research Process:
The research process began with an analysis of the original synthesis of (S)-1-indanol, which involved a general discussion of the greenness and sustainability and a life cycle analysis (LCA) from the industrial process data1. This task provided a benchmark and gave an indication of what needed to be improved from the outset. The group decided that each member would provide an analysis of a specific stage of the old synthesis and since there was an extra step, I proposed that I would analyse two stages – four and five.
From the beginning it was evident to me that none of the stages of the original synthesis appeared to have any green or sustainable aspects, the overall conclusion being that each stage in fact violated one or more of the Principles of Green Chemistry2. The synthesis involved the use of chlorinated reagents and toxic solvents, with hazardous by-products and costly waste disposal. On a personal note, I found stage four to lack greenness due to the large amount of solvent associated with four crystallisations and this is not justified by the poor yield of 25%. Additionally, the solvent used (hexane) has been classed as hazardous by the Royal Society of Chemistry3, as it is a volatile organic compound (VOC) and is a danger to aquatic life. Although the final stage (five) may use a recommended green solvent in ethyl acetate, that has minimal effect on aquatic life and less VOC emissions, its need for removal by distillation causes it to fall short in terms of energy efficiency.
LCA production allowed for a more in depth understanding of whether the process complied with the Green Chemistry Principles, in terms of both quantitative (atom economy, stoichiometry, concentration, auxiliary materials and energy usage) and qualitative (waste toxicity, materials hazards and sustainability) parameters. Each group member agreed to analyse two parameters, since there was a total of eight, and I produced the concentration and auxiliary indexes. These indexes show how much the concentration of a reaction deviates from the standard industrial aim (5M) and give the ratio of the mass of product to the mass of other materials added. Although mathematical, I found these parameters useful and the result satisfactory, as it provided a measure of greenness and acted as quantitative proof of the need for a new synthesis.
Proposals for the new synthesis then began, with each group member researching literature sources for any relevant material and bringing them together, followed by discussion in a study room. Initially a two-step synthesis was proposed (fig. 1), which employed more green and sustainable techniques and produced enantiomerically pure (S)-1-indanol. The main precursor for this process, 3-phenylpropanoic acid (hydrocinnamic acid), removes the need for chlorinated reagents and is available at a price of ?25.70 per 100g (Sigma-Aldrich).
The process itself suggested the synthesis of indanone, from Friedel-Crafts acylation of hydrocinnamic acid in an ionic solvent and selective hydrogenation to enantiomerically pure (S)-1-indanol. Although questions are often raised regarding the use of ionic liquids on an industrial scale, the Tb(OTf)3/[bmim]OTf solution can be removed from the reaction in high yield, vacuum dried and reused for the next reaction4. Therefore, recyclability of this Tb(OTf) has been validated and its costs are justified. The second stage of the above reaction takes place readily at the low temperature of 28°C, with an impeccable yield5. Although difficulties were encountered in finding exact cost or recyclability of the complex ruthenium catalyst, it was assumed to be expensive (like most ruthenium-based catalysts) and its recyclability to be of industrial standard. Having felt as though the cost was justifiable and the process much more sustainable, I was happy with the new synthesis.
However, several days before the draft deadline, one group member suggested that we try to find a way of beginning our synthesis with precursors that could be found from natural sources. Although not entirely sure that this would be feasible, in order to respect all members opinions equally, we began to think retrosynthetically and the following was proposed (Fig. 2) for hydrocinnamic acid production. Figure 2
With benzyl alcohol being naturally produced by many plants, and cerium (IV) oxide being synthesised from urea and aloe vera6, we potentially had a synthesis from natural products. Benzaldehyde could then be converted to cinnamic acid via the Perkin reaction, and catalytically hydrogenated to hydrocinnamic acid7. We produced an LCA for the above reactions, finding that although the reaction seemed feasible, there were a few complications. Primarily, the synthesis still incorporated the use of solvents such as acetonitrile, which emits toxic fumes. Moreover, the first step is not energy efficient, and several other problems were found on a practical level. The recovery of benzyl alcohol, urea and aloe vera is something which is hard to analyse from a cost and practical point of view, with little or no information available. Additionally, although the Perkin reaction is common, the group struggled to find literature information on this reaction using benzaldehyde and selectively giving the required trans isomer, so quantitative LCA data could not be completed.
I was doubtful that the suggested synthesis could be made feasible, however one member insisted that it was best to include it in our draft report and await feedback. The group agreed and began producing a report on this synthesis, the work being distributed in a similar way to previous tasks. Each member analysed two parameters for the new synthesis and compared their findings with that of the first synthesis. The aforementioned member proposed that they add their analysis last and showed a desire to submit the draft. However, the draft was not submitted, and the group not informed. This resulted in a late submission with the final member’s content missing, therefore we did not receive feedback until the day before the individual task was due. Unfortunately, a matter of days before the individual task was due, it transpired that this member would no longer be taking part.
By considering the complications encountered, I believed a compromise was required. A member down, we had to make up for their work and propose a synthesis which would obey as many green chemistry principles as possible and exhibit sustainability. Instead of using benzyl alcohol obtained from plant extracts, I suggested that we start from cinnamic acid which is also naturally occurring in many plants8. However, difficulties were again presented with regards to knowing the cost and efficiency of trying to extract trans-cinnamic acid, so alternatively it could be purchased at ?15.50 per 100g (Sigma-Aldrich) and is much cheaper than buying hydrocinnamic acid.
The final synthesis (Fig. 3) was agreed upon, as we believed it to be the best compromise, exhibiting a high degree of Green Chemistry and sustainability. The final LCA was produced for this route, and the final report compiled accordingly. This final task especially, gave the group an insight into some of the real-life difficulties of working in a team, nevertheless our task was completed, and the objectives achieved.
I am pleased to have been given the opportunity to work on a project that mimicked the tasks in a practical working environment. Not only did we produce a more green and sustainable synthesis for (S)-1-indanol, but we also overcame many of the challenges and complications that working in a team of people can present. This has undoubtedly provided the experience of teambuilding, communication and leadership, which all employers seek, preparing us for future working environments.