Arene C has the composition 90.6% carbon and 9.4% hydrogen. Its mass and 1H NMR spectra are shown below.

a.

b.

a. Calculate the empirical formula of C.

b. From the mass spectrum, find the molecular mass of C and hence its molecular formula.

c. i. Draw displayed formulae for the possible aromatic isomers of C.

ii. When C is treated with chlorine in the presence of AlCl₃ it undergoes electrophilic aromatic substitution. In this reaction one of the hydrogen atoms bonded directly to the benzene ring is replaced with one chlorine atom, and one single aromatic product is formed. Use this evidence and the NMR spectrum of C to decide which isomer is C.

d. Explain the main features of the 1H NMR spectrum of C.

Transcribed Image Text:

100- 80- 60- 40- 20- 0- 10 20 30 40 50 60 70 80 90 100 110 Mass-to-charge ratio (m/e) Relative abundance 8 8 8 9