Lab 1: Electrophilic Aromatic Substitution: Nitration of Methyl Benzoate

Nitration reactions are examples of _______________

electrophilic aromatic substitution reactions

The nitronium ion forms from the reaction of _____ ______

nitric acid

sulfuric acid

You will characterize your nitration product using…

TLC

Mixed melting point

What solvent will you use to dissolve your product prior to spotting it on your TLC plate?

acetone

Based on your knowledge of the effects of substituents on electrophilic aromatic substitution reactions, the product of the nitration of methyl benzoate should be primarily ____________

methyl m-nitrobenzoate

Benzene undergoes electrophilic substitution reactions. (T/F)

true

The second step of electrophilic aromatic substitution (EAS) is different from the electrophilic addition (EA) reaction of alkenes. How?

In EAS, the second step regenerates aromaticity.

Which of the following describes the rate determining step of electrophilic aromatic substitution? 

• The aromatic ring is the nucleophile

• The pi electrons of the aromatic ring attack the electrophile

• A carbocation is generated

In an electrophilic aromatic substitution reaction, how might ring substituents affect the reaction?

• Electron-donating groups can increase the electron density of the ring and enhance the reaction rate

• Electron-withdrawing groups can decrease the electron density of the ring and decrease the reaction rate

What type of functional group is present in methyl benzoate?

ester

Is the functional group in methyl benzoate electron donating or electron withdrawing? What type of directing group is it?

Deactivator (electron withdrawing group) and directs meta.

In addition to mononitration products, the dinitro compound is a minor product of this reaction. What techniques can be used to reduce or avoid the production of the dinitro compound?

The dinitro product was prevented from forming by using ice baths throughout and adding the nitrating solution slowly