Synthetic routes map out synthetic pathways

Chemists create complex compounds, which are often used in medicines or agricultural chemicals.

Typically, synthesising the target compound directly from a single starting material in one step is not feasible.

A synthetic route outlines the sequence of reactions needed to transform starting materials into the desired end product.

It details:

• Every chemical intermediate formed along the way.
• The specific reagents and conditions required at each stage of the process.

For instance, converting 2-chloropropane to propanone isn't a straightforward, one-step process.

Instead, a two-step synthetic route is necessary:

1. 2-chloropropane reacts with KOH, producing propan-2-ol.
2. Propan-2-ol, when treated with acidified K₂Cr₂O₇, yields propanone.

Summary of key organic reactions

Below is an overview of the primary types of organic reactions we've discussed:

Functional groups dictate reactivity

The behaviour and properties of functional groups significantly affect molecular reactions.

For example:

• Nucleophiles are attracted to the partially positive carbon in halogenoalkanes, but they don't target the electron-rich C=C double bond in alkenes.
• Alcohols, due to their polar O-H bond and the lone pair of electrons on the oxygen atom, can act as nucleophiles.

The following table outlines common reactions associated with key functional groups:

Accurately predicting the reactivity of compounds with multiple functional groups requires identifying each group.