Question

What is the structural diagram of 2-phenylethanal and 2-phenylacetaldehyde?

Answer 1

Hint: Structural diagram of a chemical compound helps to identify the location of chemical bonds between the atoms in a molecule. The organic compounds are generally represented by simplified structural diagrams which not only show the kind and number of atoms present in the molecule but also depicts the way in which the atoms are linked via covalent bonds.

Complete answer:
To draw the structural diagrams of the given molecules, we first need to analyse the functional group which is indicated by the name of the given molecules. In 2-phenylethanal, the suffix “al” shows that the compound consists of an aldehyde group and compound 2-phenylacetaldehyde consists of an aldehyde functional group as well as clearly mentioned by the common name of the molecule.
Now, the prefix of both the molecules indicates the position of substituent group i.e., a phenyl ring is attached to second position of the given aldehyde molecules and as we know that ethanal is the simplest aldehyde molecule which is commonly known as acetaldehyde. So, both the names are indicating the same structure. Hence, the structural diagrams of both the given molecules is same and can be represented as follows:

Note:
Remember that the aldehyde group is always attached at the end of the main carbon chain and while naming the compound, the first position is always assigned to the carbon of the carbonyl (aldehyde) group. However, for simpler molecules, it is not always necessary to include numbering in naming.