Category Archives: chemistry

Molecular Chemistry and Supramolecular Chemistry

Molecular chemistry

Radboud University calls molecular chemistry a ‘creative science’ “where chemists synthesize molecules with new biological or physical properties to address scientific or societal challenges. Working with chemical structures, the possibilities are endless: in principle, every molecule can be made. The challenge is to adapt the 3D-structure to the desired properties and design an efficient synthesis method” (https://www.ru.nl/publish/pages/756119/masterflyer_molecular_chemistry.pdf). The Arizona State University specifically states that “he traditional disciplines of chemistry and biochemistry are evolving and maturing. In response, the Department of Chemistry and Biochemistry at Arizona State University has reorganized into the new School of Molecular Sciences”, within which it studies nanoscience, molecular understanding of disease, diagnosis and therapeutics, molecular energy and catalysis, to mention a few (https://sms.asu.edu/). The University of Sorbonne says that “Molecular chemistry is at the crossroads of contemporary science marked by an increasing miniaturization. Its object of study is the molecule, which represents the common base of the sciences of the future, from medicine and pharmacology to nanotechnology and materials. All these fields have a growing need for fabricated molecules with specific properties” (http://www.upmc.fr/en/education/diplomas/sciences_and_technologies/masters/master_of_chemistry/molecular_chemistry_specialization_m2.html). Among the most interesting recent developments is the application of topological methods to molecular chemistry (http://www.springer.com/in/book/9783319290201)

The Justus-Liebig-Universitat Giessen is interested in the study of dispersion interactions in molecular chemistry. Talking of its DFG programme, it states that “Dispersion is the driving force for molecular aggregation that plays a key role in the thermodynamic stability, molecular recognition, chemical selectivity through transition-state stabilization, protein folding, enzyme catalysis etc.. While dispersion interactions help rationalize many common phenonema such as well-established π-π interactions, the related σ-π systems have been examined much less and the concept of σ-σ attraction is in its infancy. A primary goal of this program is the development of chemical design principles that utilizes dispersion interactions in the construction of novel molecular structures and chemical reactions” (http://www.uni-giessen.de/fbz/fb08/dispersion). The department of Chemistry of the Indiana University Bloomington has a “Molecular Structure Center’ which has a laboratory which “has a full complement of single crystal and powder diffraction equipment used to characterize crystalline materials using the techniques of X-ray crystallography. Researchers in the laboratory can determine the three-dimensional structure of nearly any material that can be crystallized” (https://www.chem.indiana.edu/facilities/research-facilities/molecular-structure-center/).

Supramolecular chemistry

Now researchers talk of ‘supramolecular chemistry’. Nature magazine defines it thus: “Supramolecular chemistry is the study of entities of greater complexity than individual molecules — assemblies of molecules that bond and organize through intermolecular interactions. The design and synthesis of supramolecular systems invokes interactions beyond the covalent bond, using, for example, hydrogen bonding, metal coordination and π interactions to bring discrete building blocks together” (https://www.nature.com/subjects/supramolecular-chemistry). The Beilstein Journal of Organic Chemistry said in 2009 that “important concepts that have been demonstrated by supramolecular chemistry include molecular self-assembly, self-sorting and recognition, templated synthesis or host-guest chemistry. These concepts have made supramolecular synthesis a powerful tool to construct large and complex chemical architecture from simple building blocks or to develop functional supramolecules. Among these are molecular switches, logic gates, molecular containers, elevators, valves and springs, supramolecular catalysts and many more” (https://www.beilstein-journals.org/bjoc/series/6). Texas A&M University’s research into supramolecular chemistry ranges from catalysis to rare earth metal compounds to polymers to energy-related research (http://www.chem.tamu.edu/faculty/supramolecular.php). The Pierre Research Group at The University of Minnesota looks at the environmental applications of supramolecular chemistry. It “conducts research to develop approaches to selectively remove phosphate from polluted lakes and rivers and later release it at will on farmlands in the form of fertilizers.  Specifically, we are developing novel metal-based supramolecular self-assemblies for the reversible and selective capture of phosphate from aqueous systems.  The approach employs the coordination chemistry of hard metal ions with open coordination sites together with other supramolecular principles such as complementarity in shape and hydrogen-bonding for selective sequestering of phosphate over other oxyanions.  The ultimate goal is to produce porous membranes that can selectively remove phosphate from polluted lakes and rivers and reuse them in the form of fertilizer.  This work advances the field of supramolecular chemistry by investigating the structural parameters of metal-based supramolecular assemblies that govern selectivity and reversibility in binding of oxyanions” (http://pierre.chem.umn.edu/research/environmental-applications-supramolecular-chemistry).

The European Commission’s Digital4Science links supramolecular chemistry with mesotechnology. According to them, “Our growing ability to design synthetic molecules and macromolecules opens new pathways for the generation of enhanced functional materials. The tailored design of (macro)molecules enables the precise control of chemical and physical properties and thus, molecular interactions. Besides classical macromolecular and colloidal materials, supramolecular structures which originate from solely physical interactions can be formed. These materials are built by precise self-assembly and display complex architectures with hierarchical structuration on multiple length scales leading to a wealth of novel structures and functions” (https://ec.europa.eu/futurium/en/content/supramolecular-chemistry-and-mesotechnology). The Yamakoshi Research Group at ETH researches ‘synthetic receptors and thermos sensors’ (http://www.yamakoshi.ethz.ch/Research_Dec2017/supramolecular-chemistry.html).

At the University of Lyon in France, The Institute for Molecular and Supramolecular Chemistry and Biochemistry conducts research in broad fields that are linked to both chemistry and biochemistry: Synthesis, methodology and catalysis; Biomolecules: synthesis, properties and assemblies; and Biological and biomimetic membranes, biocatalysis (https://www.univ-lyon1.fr/research/institute-for-molecular-and-supramolecular-chemistry-and-biochemistry-icbms–801104.kjsp). The Research Center for Functional Molecular Systems in Netherlands has been recognizing outstanding research in supramolecular chemistry (https://fmsresearch.nl/netherlands-award-for-supramolecular-chemistry/).

Research in Chemistry

You will be amazed at the diversity of research in chemistry, although today the subject is dramatically different from what it was even a few decades ago. Similar to the manner in which all basic sciences are evolving, chemistry too is engaged with multiple disciplines and technologies. By its very nature research in chemistry involves laboratory research as it seeks to explore areas as far removed as food and solar cells. While traditional areas such organic and inorganic chemistry continue to grow just as does analytical chemistry not to mention computational chemistry, it is in its interfaces with biological and material sciences that you see serious developments. In some countries, given geography, you will find chemistry interacting with marine themes. Water is a major theme in some industries. If you love chemistry, these are exciting times to be a student.

In September 2015, the ACS journal spoke of the 15 hottest research topics in chemistry, which include, among others, research in battery science and technology, linking the biological and synthetic worlds, residues in food and feed, the dynamics and mechanisms through which inorganic molecules absorb and dissipate radiant energy, and many others (http://axial.acs.org/2015/09/04/15-hottest-research-topics-chemistry/). Considering the time any research takes, it is extremely likely that these continue to be sought after topics, even if others have cropped up.

While asking “What are the hottest current research topics in chemical engineering and chemistry?”, a post in quora.com makes a significant observation. It talks of the slow death of the engineering core of chemical engineering. According to this post, the biggest science players in CE are biological sciences as they can impact medicine and neuroscience, areas where governments are willing to support research (https://www.quora.com/What-are-the-hottest-current-research-topics-in-chemical-engineering-and-chemistry).

The Department of Chemistry and Biochemistry at California State University, Long Beach, has set up a very fundamental goal: “Applying conventional disciplines of chemistry to current and future issues”. Governed by this theme, it has research interests in Biochemical & Biophysical sciences, Drug design & delivery, Energy & environment, Material sciences, Nanoscience & technology, Organic synthesis characterization and catalysis (http://chemistry.csulb.edu/research.html). The Department of Physical Chemistry, Fritz Haber Institute of the Max Plank Society states its research goal thus: “We proceed from the notion that most of the chemistry that shapes the earth surface environment, places the physical limits on life and underlies many of the devices we use happens at interfaces. To understand this chemistry we mostly use (non)linear optical techniques based on fs pulsed laser sources. In addition, depending on the system, we also employ a wide variety of additional experimental probes as necessary. Current work focuses on the following six areas…

[i] Water Interaction with Metal Oxide Surfaces

[ii] Probing (Photo) Electrochemical Chemistry at Solid/Water Interfaces

[iii] Structure and Dynamics of Water and Solutes at the Air/Water Interface

[iv] Molecular Switches at Solid/Liquid Interfaces

[v] Building a Better Spectrometer to Probe Interfaces in Condensed Media

[vi] Hydrocarbon Decomposition on Metal Surfaces

(http://w0.rz-berlin.mpg.de/pc/campen/current-research/).

Wiley-VCH explores the relationship between chemistry and material sciences (https://application.wiley-vch.de/util/hottopics/). Some of the major topics this examines are synthetic chemistry and catalysis, bio-and-medicinal chemistry, sustainable chemistry and materials. Another journal you should read is the International Journal of Current Research in Chemistry and Pharmaceutical Sciences http://www.ijcrcps.com/, as it explores various themes in chemistry together with themes in pharmaceutical sciences. Interestingly, the Freie University in Berlin has a Department of Biology, Chemistry and Pharmacy, which has several research projects which have good external sources of funds. Some of the areas it researches are Fungal ecology in agricultural systems, Ecological synthesis and analysis, Trait-based approaches to fungal ecology and others (http://www.bcp.fu-berlin.de/en/biologie/arbeitsgruppen/botanik/ag_rillig/forschung/current_projects/index.html).

The University of Turku is interested in exploring Food chemistry and Food development (http://www.utu.fi/fi/yksikot/sci/yksikot/biokemia/tutkimus/ekeh/Sivut/home.aspx). The University of British Columbia has an extremely focused research goal: “the development of organometallic nitrosyl complexes as specific reactants or selective catalysts for chemical transformations of practical significance”, (https://www.chem.ubc.ca/current-research-interests). The The Department of Chemistry at KTH has research interests in Dynamic chemistry; Biomimetic, supramolecular chemistry; Arrays, sensors and biointerfaces; Advanced materials; Organic synthesis; Molecular recognition and biological interactions (https://www.kth.se/en/2.80884/orgkem/research/ramstrom/current-research-areas-1.26717). Research at The Department of Chemistry at the Norwegian University of Science and Technology is based on organic synthetic chemistry and “focused on reaction design and methodology development in the fields of medicinal technology, molecular nanotechnology and energy related sciences”, (https://www.ntnu.edu/chemistry/research/organic-chemistry).

Chemistry research group at IIT Bombay “has been interested in synthesis of novel core-modified porphyrins to explore their potential for various applications in place of normal porphyrins (N4 core). We are working on different aspects of core-modified porphyrin chemistry and developed some new method(s) to synthesize new heteroporphyrin systems with desirable functional groups as well as some complicated heteroporphyrin based systems” (http://www.chem.iitb.ac.in/~ravikanth/homepage/research-activities.html). The Indian Institute of Science Education and Research, Pune has brought together Chemistry, Chemical biology and Material science under which it has organized its research in these topics: Laser spectroscopy of isolated and solvated biomolecules in the gas phase, Photoelectron spectroscopy of complex polyatomics using synchrotron radiation, Design, synthesis and characterization of porphyrinoids, photo dynamic therapy, Synthesis of luminescent materials for organic light emitting diodes, Biomolecular chemistry of nucleic acids, peptides carbohydrates, and lipids, Nucleic acid therapeutics and diagnostic, Synthesis and conformational analysis of hybrid peptides containing non-natural amino acids, Design and synthesis of peptides of medical relevance: small molecule inhibitors for HIV-1 and host cell interactions, Synthetic methodology, total synthesis of natural products, small molecule inhibitors for Proteases and Glycosidases, Biomimetics, Bio-inspired Chemistry and Nanoscience and Computational chemistry of condensed phase systems (http://www.iiserpune.ac.in/research/disciplines/chemistry).

We could go on. You could further explore, based on these and your interests. Meanwhile, apart from www.sciencedaily.com, which is a useful resource on science in general, you may look up www.chemistryworld.com for the latest information.

Green Chemistry

The concern for the environment has been gathering momentum for many years and the world of education and research is responding with a sharp focus on many critical dimensions. You may choose any definition of green chemistry as long as you remember that definitions can and do change with further developments. While we all use the term ‘sustainable’, we need to also understand that conditions of sustainability don’t remain stagnant. In what follows, we offer a peek into this exciting area of research which can actually make a difference to the way the environment is protected even as economic progress takes place. Given that almost every discipline today has interconnections with some other discipline or disciplines, the breadth of the subject has grown. The key aspect to emphasise is the need for balance.

PES University defines it simply thus: “Green Chemistry research domain aims to develop and implement green and sustainable chemistry and related technologies into new products and processes” (http://pes.edu/research/green-chemistry/). Green chemistry involves the development of chemical products and processes that minimize the use and generation of hazardous and unwanted substances (https://www.nature.com/subjects/green-chemistry).

Some of the areas of green chemistry are: Combinatorial green chemistry, Green Chemistry in Agrochemicals, Sustainable Flow Chemistry, Ultrasound Technology in Green Chemistry and Wood Products and Green Chemistry. The Royal Society of Chemistry, the UK, publishes the international scientific journal Green Chemistry which “publishes research that attempts to reduce the environmental impact of the chemical enterprise by developing a technology base that is inherently non-toxic to living things and the environment” (http://www.internetchemistry.com/rss/green-chemistry.php). The American Society for Chemistry says that “The main goals and applications of green chemistry are to reduce environmental, human health and safety risks of chemicals by redesigning toxic molecules, synthetic routes, and industrial processes. Green chemistry is an interdisciplinary field, drawing on knowledge from chemistry, chemical engineering, toxicology, and ecology”, (https://www.acs.org/content/dam/acsorg/membership/acs/benefits/extra-insights/green-chemistry.pdf).

The Institute of Bioengineering and Nanotechnology discusses its interest in research in green chemistry and energy “which encompass the development of catalysts and nanocomposites for the green synthesis of chemicals and pharmaceuticals, biomass and carbon dioxide conversion, water purification, and energy applications” (http://www.ibn.a-star.edu.sg/research_areas_3.php?expandable=1). Another but different set of research interests comes from the magazine ‘Green Chemistry’, which, in its January 2017 issue spoke of the 25 years of the E-factor, a concept introduced in 1992 to better measure the ‘efficiency in organic synthesis’, bringing in the environment factor. It says: “Clearly, an environmental factor was missing and this led us, in the late 1980s, to propose the E(nvironmental) factor – mass of waste/mass of product, usually expressed as kgs/kg – for assessing the environmental impact of manufacturing processes” (https://moodle.drew.edu/2/pluginfile.php/234983/mod_resource/content/1/Green%20Chem%20E%20Factor%2025%20Years%20Sheldon%20GC%202017%20c6gc02157c.pdf). Professor James Clark of the University of York, the UK, speaks of ‘closed loop chemistry’ using it to discuss how to go from waste to wealth using green chemistry (http://www.tsn.org.uk/downloads/Waste-to-Wealth.pdf). The Mellon College of Science at Carnegie Mellon University conducts “research into renewable energy sources, environmentally sound chemical processes and remediation of chemical waste” (https://www.cmu.edu/mcs/research/areas/greenchem-environment/index.html).

There was a national conference on recent trends in green chemistry and sustainability in India in 2017 which furnishes a useful list of green chemistry applications (http://www.geu.ac.in/event-detail.aspx?mpgid=95&pgidtrail=200&Eventsid=1266). The Journal of the Royal Society of Interface has an interesting essay on ‘Engineering a more sustainable world through catalysis and green chemistry’ (http://rsif.royalsocietypublishing.org/content/13/116/20160087). Greenbiz.com has an educative article titled “Partnerships: The key to getting green chemistry tech to market?”, which says that “Bringing greener chemicals, materials and process technologies to market and scale is not for the meek” (https://www.greenbiz.com/article/partnerships-key-getting-green-chemistry-tech-market). This is a generally useful website.

Researchgate, a forum for researchers, speaks specifically of green chemistry and new technological developments, discussing new avenues for green economy and sustainable future of science and technology (https://www.researchgate.net/profile/Athanasios_Valavanidis/publication/305207284_Green_Chemistry_and_New_Technological_Developments_New_Avenues_for_the_Green_Economy_and_Sustainable_Future_of_Science_and_Technology/links/5784a1b908ae37d3af6d7f34/Green-Chemistry-and-New-Technological-Developments-New-Avenues-for-the-Green-Economy-and-Sustainable-Future-of-Science-and-Technology.pdf).

12 Principles of Green Engineering

Several years ago, some researchers enunciated 12 Principles of Green Engineering, which should give anyone a fair idea of the kind of research that needs to be conducted. These are:

  1. Inherent Rather than Circumstantial – Designers need to strive to ensure that all materials and energy inputs and outputs are as inherently nonhazardous as possible.
  2. Prevention Instead of Treatment – It is better to prevent waste than to treat or clean up waste after it is formed.
  3. Design for Separation – Separation and purification operations should be designed to minimize energy consumption and materials use.
  4. Maximize Efficiency – Products, processes, and systems should be designed to maximize mass, energy, space, and time efficiency.
  5. Output-Pulled Versus Input-Pushed- Products, process and systems should be “output pulled” rather than “input pushed” through the use of energy and materials.
  6. Conserve Complexity – Embedded entropy and complexity must be viewed as an investment when making design choices on recycle, reuse, or beneficial disposition.
  7. Durability Rather than Immortality – Targeted durability, not immortality, should be a design goal.
  8. Meet Need, Minimize Excess – Design for unnecessary capacity or capability (e.g., “one size fits all” solutions) should be considered a design flaw.
  9. Minimize Material Diversity – Material diversity in multicomponent products should be minimized to promote disassembly and value retention.
  10. Integrate Material and Energy Flows – Design of products, processes, and systems must include integration and interconnectivity with available energy and material flows.
  11. Design for Commercial “Afterlife”- Products, processes, and systems should be designed for performance in a commercial “afterlife”.
  12. Renewable Rather Than Depleting – Material and energy inputs should be renewable rather than depleting.

Anastas, P.T., and Zimmerman, J.B., “Design through the Twelve Principles of Green Engineering”, Environmental Science & Technology 2003, 37, 94A-101A (https://www.acs.org/content/dam/acsorg/membership/acs/benefits/extra-insights/green-chemistry.pdf).