Chemistry B

(course website: http://www-teach.ch.cam.ac.uk/introcourses/index.html)

This subject looks at how chemists investigate and rationalise the many kinds of reactions that we know. The worlds of organic, inorganic and biochemistry are all covered in Chemistry B and hence this subject overlaps more with biological subjects than Chemistry A. You will have one supervision a week for which your supervisor will set the questions to be completed. It is important to make an attempt at all the questions even if you are not sure on the answer as this will help the supervisor see your way of thinking and direct the supervision efficiently. This is a subject where writing notes after your supervision is immensely helpful as there are many cases where a supervisor will explain something in simpler terms than a book is able to.

Throughout the Michaelmas and Lent terms there are compulsory practical classes in the chemistry department where you will learn to synthesise, separate, purify and identify organic and inorganic chemicals. You will alternate between organic and inorganic practicals which will be marked the next week. The marking procedure takes the form of a short interview where you will be required to provide a sample of your product and certain information about it that you have measured (like melting point) and you will be questioned on your understanding of the underlying chemistry that has taken place.

The first lecture series is Key Organic Reactions (12 lectures). You will study flat chemistry which covers how to direct substitution and addition reactions to particular places on a molecule and the important chemistry of enols and enolates. You will then study chemistry in three dimensions where you look at how the handedness (or chirality) of molecules can affect their structure and reactivity.

The second lecture series is Structure Determination (6 lectures). This course teaches you about the variety of methods for working out the structure of a molecule and the ways to interpret them. These are mass spectrometry, UV spectroscopy, C-13 NMR spectroscopy and proton NMR spectroscopy.

Next comes Co-ordination Chemistry (8 lectures) which focuses on the first row transition metal complexes to look out how orbital interactions control their geometry. You will discuss the concept of Crystal field Stabilisation Energy and use it to determine what geometry will be preferred and the extent to which the d-orbitals are split. You will then see how d-orbital splitting has an effect on ionisation energy, oxidation state and the magnetic properties of complexes.

The fourth set of lectures is Organometallic Chemistry (6 lectures). These substances are compounds with metal to non-metal bonds which have a considerable covalent character. You will study everything from their synthesis and characterisation to the structures they adopt and the various ways of considering their bonding.

This is followed by Inorganic Ring Chemistry (6 lectures) which studies p-block ring systems. Their syntheses, structures and in particular their bonding are examined. Much of the understanding of these molecules is up for debate so you will study how different arguments are rationalised and discuss their relative merits and shortcomings.

Shape and Organic Reactivity (10 lectures) is the penultimate lecture series which builds heavily on the Key Organic Reactions course. It looks at the relationship between the shape of a molecule and its reactions. In two dimensions molecules with π-bonds are looked at as well as the thermodynamic and kinetic factors affecting their production. In three dimensions there are a variety of ways shape controls reactivity and many of these are considered.

Lastly comes Introduction to Chemical Biology (11 lectures). The structure, function and chemistry of DNA, RNA and proteins are studied as is the role of metal ions and non-covalent interactions for these biopolymers. Basic physical organic concepts, such as transition state theory, are looked at with reference to enzyme chemistry.