Table of Contents

USING THE CAMBRIDGE STRUCTURAL DATABASEFOR TEACHING

Conditions of Use

INTRODUCTION

TEACHING SUBSET OF THE CSD

CLASSROOM CONQUEST

TEACHING MODULES

AROMATICITY

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Examine the structure of benzene

Examine the structure of cyclooctatetraene.

Consider what happens when we treat cyclooctatetraene with a powerful reducing agent

Consider what happens if we treat benzene with oxidizing or reducing agents

Do you see a pattern forming?

Molecular orbital description

Requirements for aromaticity

Use Huckels rule to predict aromaticity

SUMMARY OF KEY CONCEPTS

SHAPES OF MOLECULES: VSEPR MODEL

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Examine the structures of di-, tri-, and tetrachloro mercury

The VSEPR model

Apply the VSEPR model to predict basic shape

Modifications to basic shapes: considering the effect of lone pairs

Further examples

SUMMARY OF KEY CONCEPTS

METAL CARBONYL BACK-BONDING

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Define a search for molybdenum carbon monoxide complexes

Define the relevant bond lengths of interest (the MoC and CO bonds) and apply some constraints

Set the search running and analyse the results

Try and rationalise what you are seeing

ADVANCED EXCERCISES

What are the other resonance forms of CO?

How could the phenomenon of pi backbonding be studied in the laboratory?

Analyse other transition metal carbonyl complexes: does this effect occur for all metals?

SUMMARY OF KEY CONCEPTS

DETERMINING MOLECULAR DIMENSIONS

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Background

What is the typical Sb-Cl bond length in hexachloro-antimony?

Evaluating the precision of the data.

Evaluate the outliers in the Sb-Cl bond length distribution.

Evaluate the structure that contains the longest observed Sb-Cl bond length.

SUMMARY OF KEY CONCEPTS

ANALYSING 4-COORDINATE METAL GEOMETRY

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Find 4-coordinate transition metal complexes in the CSD

Run the search

Define geometric parameters

Run the search and export the data

Analyse the geometric data

SUMMARY OF KEY CONCEPTS

REACTION INTERMEDIATES: HALONIUM IONS

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Electrophilic Addition of Br2 to an Alkene

Investigate the stereochemistry of halogen addition

Search for evidence, in the Cambridge Structural Database, that the cyclic bromonium ion actually does exist.

Find other examples of halonium ions

Explain the stability of the halonium ions found in the CSD.

SUMMARY OF KEY CONCEPTS

HAPTICITY

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Investigating metal-carbon bonding

Acyclic ligands

Cyclic ligands

Variable hapticity

Heteroatoms in rings

SUMMARY OF KEY CONCEPTS

CONFORMATIONS OF RINGS

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Investigate angle strain in planar rings.

Calculating angle strain in actual compounds

Compare predicted angle strain against that calculated from actual compounds

Examine the conformation of cyclopropane

Examine the conformation of cyclobutane

Examine the conformation of cyclopentane

Examine the conformation of cyclohexane

SUMMARY OF KEY CONCEPTS

SUPPLEMENTARY MATERIAL: DETERMINING THE PREFERRED INTERNAL BOND ANGLE IN CYCLOHEXANE USING THE FULL CSD

STEREOCHEMISTRY

INTRODUCTION

OBJECTIVES

GETTING STARTED

STEPS REQUIRED

Investigate the structure of the amino acid alanine.

Identifying chirality.

Describing the configuration of a chiral centre.

Compounds containing more than one stereogenic center.

Compounds that contain stereogenic centers but are achiral.

ADVANCED EXCERCISE

Compounds with quadrivalent chiral atoms other than carbon.

Substituted adamantanes.

Compounds with tervalent chiral atoms.

Chirality due to restricted rotation,

Chirality due to helical shape.

SUMMARY OF KEY CONCEPTS