Q55E - Organic Chemistry (Mcmurry)

Question

Draw and name the seven aldehydes and ketones with the formula ${\mathbf{C}}_5{\mathbf{H}}_{10}\mathbf{O}$ . Which are chiral?

Step-by-Step Solution

Answer

The seven aldehydes and ketones with ${\text{C}}_{\text{5}}{\text{H}}_{\text{10}}\text{O}$ formula are,

The only chiral compound is 2-methylbutanal.

Step-by-Step Solution Step 1: Chiral compounds

Chiral compounds are those in which carbon atoms contain four different groups and have no plane of symmetry. They are non-superimposable and are absent in ketone containing carbon because the carbon is ${\text{sp}}^{\text{2}}$ .

Step 2: Aldehydes and ketones with the formula C 5 H 10 O

The four aldehyde compounds with ${\text{C}}_{\text{5}}{\text{H}}_{\text{10}}\text{O}$ formula are pentanal, 2-Methylbutanal, 3-Methylbutanal and 2,2-Dimethylpropanal.

                                    Aldehyde compounds with ${\text{C}}_{\text{5}}{\text{H}}_{\text{10}}\text{O}$

The three ketone compounds with formula ${\text{C}}_{\text{5}}{\text{H}}_{\text{10}}\text{O}$ are 2-Pentanone, 3-Pentanone and 3-Methyl-2-butanone.

Ketone compounds with ${\text{C}}_{\text{5}}{\text{H}}_{\text{10}}\text{O}$

Only 2-Methylbutanal is a chiral compound among the seven compounds because the second carbon has four different groups attached.

Chiral compound