Module Details

The information contained in this module specification was correct at the time of publication but may be subject to change, either during the session because of unforeseen circumstances, or following review of the module at the end of the session. Queries about the module should be directed to the member of staff with responsibility for the module.
Title Further Organic Chemistry
Code CHEM333
Coordinator Dr RP Bonar-Law
Chemistry
R.P.Bonar-Law@liverpool.ac.uk
Year CATS Level Semester CATS Value
Session 2021-22 Level 6 FHEQ First Semester 15

Pre-requisites before taking this module (or general academic requirements):

CHEM231 CHEM231 - Organic Chemistry II 

Aims

The aim of the module is to extend second year knowledge of synthetic and physical organic chemistry.


Learning Outcomes

(LO1) By the end of the module, students should be able to show:
* a good understanding of modern synthetic reactions and their mechanisms.
* deduce mechanisms on the basis of kinetic and other evidence.


Teaching and Learning Strategies

This module consists of 35 50-minute lectures in the first semester. 
The material presented at the lectures is supported by 5 1-hour tutorials.
Both lectures and tutorials online in 2021-21.


Syllabus

 

Organic synthesis and reactions (20 lectures + revision lecture)

- Pericyclic reactions 1: cycloadditions. The rules that govern cycloadditions. Photochemical reactions: reactions that need light. Making six-membered rings by the Diels–Alder reaction. Making four-membered rings by [2 + 2] cycloaddition. Making five-membered rings by 1,3-dipolar cycloaddition. Using cycloaddition to functionalize double bonds stereospecifically. Using ozone to break C=C double bonds.
- Pericyclic reactions 2: Sigmatropic and electrocyclic reactions. Stereochemistry from chair-like transition states. Making γ,δ-unsaturated carbonyl compounds. What determines whether these pericyclic reactions go ‘forwards’ or ‘backwards’. Fischer Indole synthesis. Why substituted cyclopentadienes are unstable What ‘con’ and ‘dis’-rotatory mean. Reactions that open small rings and close larger rings.  
- Rearrangements and Fragmentations: Participation means acceleration and retention of stereochemistry and may mean rearrangement. Participating groups can have lone pairs or π-electrons. Carbocations often rearrange by alkyl migration. Ring expansion by rearrangement. Using rearrangements in synthesis. Electron donation and electron withdrawal combine to create molecules that fragment. Anti-periplanar conformation is essential. Small rings are easy to fragment, medium and large rings can be made in this way. Double bond geometry can be controlled Using fragmentations in synthesis.  
- Radical reactions: Radical reactions follow different rules to those of ionic reactions. Bond strength is very important. Radicals can be formed with Br, Cl, Sn, and Hg. Efficient radical reactions are chain reactions. There are electrophilic and nucleophilic radicals. Radicals favour conjugate addition. Cyclization is easy with radical reactions. Dissolving metal reductions with met al-ammonia systems applied to aromatic systems (Birch reduction) and enones and their synthetic applications. Dissolving metal reductions applied to carbonyl groups - Pinacol coupling and acyloin condensation.  
- Phosphorus: Wittig, Wittig-Horner and Wadsworth-Emmons reactions and their use in synthesis. Aza-Wittig reaction. Mitsunobu reaction, mechanism and applications.
- Sulfur: Introduction to organosulfur compounds (oxidation states, names etc.). Synthesis and chemistry of sulfoxides, allylic sulfoxide-sulfenic ester rearrangement. Pummerer reaction, syn elimination of sulfoxides.   Sulfones - Julia reaction, Ramberg Backlund reaction and extrusion of SO2 from sulfolenes. Chemistry of sulfur ylids, Corey/Trost reagents.  
- Selenium: Comparison of sulfur and selenium compounds. Reactions of selenoxides, syn elimination and [2,3] sigmatropic rearrangements. Oxidation reactions of selenium dioxide. Selenium mediated cyclisation reactions (PhSeCl etc.).

Physical organic chemistry (13 lectures+revision lecture)

- Equilibria, transition states and rates: Free energy diagrams, transition states, connection between equilibrium and rate constants, K = k1/k-1, Hammond’s postulate, thermodynamic vs kinetic control, Curtin-Hammett.        
- Kinetics: Revision of elementary kinetics, steady state for multistep reactions, primary deuterium kinetic isotope effect.          
- S-N-2, S-N-1: Mostly revision of year 2 material  
- Elimination reactions: Revision of E1, E2, E1cb, kinetics, mechanistic continuum       
- Addition reactions: Revision of HX, X 2 additions with kinetics, some synthetic applications  
- Nucleophilic substitution at carbonyls: Tetrahedral intermediates and mechanisms for ester hydrolysis.  
- The Hammett equation: Substituent constants, reactio n constants, correlation of rates and equilibria, multistep reactions, physical basis of LFER.


Recommended Texts

Reading lists are managed at readinglists.liverpool.ac.uk. Click here to access the reading lists for this module.

Teaching Schedule

  Lectures Seminars Tutorials Lab Practicals Fieldwork Placement Other TOTAL
Study Hours 35

  5

      40
Timetable (if known)              
Private Study 110
TOTAL HOURS 150

Assessment

EXAM Duration Timing
(Semester)
% of
final
mark
Resit/resubmission
opportunity
Penalty for late
submission
Notes
Formal examination  180 minutes    80       
CONTINUOUS Duration Timing
(Semester)
% of
final
mark
Resit/resubmission
opportunity
Penalty for late
submission
Notes
5 Problem sets Standard UoL penalties apply for late submission. There is no re-submission opportunity. These assignments are not marked anonymously  supported by 5x1 hou    20