Deduce a possible structure for X that is consistent with the mass, IR and \(^{\text{1}}{\text{H}}\,{\text{NMR}}\) spectra.

Complete the table above by suggesting the chemical shift of the third peak, and state its relative peak area and splitting pattern.

Explain the splitting pattern of the peak at chemical shift 4.1 ppm.

 ;

ECF from structure in (c)(i).

(quartet means) neighbouring C;

has 3 H atoms/protons;

Award [1] for stating CH₃CH₂.

Award [2] for stating CH₃CH₂ group and indicating number of protons.

In part (c), most of the better candidates deduced the structure as CH₃COOCH₂CH₃ and subsequently the correct chemical shift, relative peak area and splitting patter for the third peak.

In part (c), most of the better candidates deduced the structure as CH₃COOCH₂CH₃ and subsequently the correct chemical shift, relative peak area and splitting patter for the third peak.

The splitting pattern of the peak at 4.1 ppm was usually well answered. Many students displayed very good knowledge of \(^{\text{1}}{\text{H}}\,{\text{NMR}}\) spectra in this question.