Organic Chemistry II - Lab 6 - Nucleophilic Aromatic Subsitution - Review

In nucleophilic aromatic substitution, the ____________ aromatic ring ____________ an added _______________.

1. Electrophilic

2. is attacked by

3. nucleophile

The resulting intermediate has a __________ charge and the replace substituent usually leaves as __________.

1. Negative

2. An Anion

Two mechanism to Explain a NAS

1. Addition-elimination (The one we will use in lab)

2. Elimination Addition

When comparing ethanol, CH3CH2OH, and sodium ethoxide, NaOCH2CH3 ________________ is the better nucleophile because it ____________.

sodium ethoxide, has a negative charge

When comparing sodium methoxide, NaOCH3, and sodium t-butoxide, NaOC(CH3)3, ___________ is the better nucleophile because it ___________.

1. Sodium methoxide

2. is smaller.

A nucleophile added to this reaction will most likely start by attacking carbon ________ because that carbon has a ___________ and is __________ to the nitro group.

1. 4

2. a leaving group

3. para

Electron withdrawing groups on the aromatic group increase reactivity.

Nucleophilic aromatic substitution

The aromatic ring is the electrophile and the added group is the nucleophile.

Nucleophilic aromatic substitution

Electron donating groups on the aromatic group increase reactivity

Electrophilic aromatic substitution

The aromatic ring is the nucleophile and the added group is the electrophile.

Electrophilic aromatic substitution

The position of the added group is mostly determined by the location of a leaving group.

Nucleophilic aromatic substitution

The position of the added group is mostly determined by electronics.

Nucleophilic aromatic substitution

Magnesium Sulfate is used in this experiment as a

Drying Agent

The position of the added group is mostly determined by electronics.

Electrophilic aromatic substitution

Determine whether each melting point observation corresponds to a pure sample of a single or Impure sample with multiple compound.

1. Experimental melting point is below literature value

Impure sample of multiple compounds

Wide Melting Point range

Impure sample of multiple compounds

Experimental melting point is close to literature value

Pure sample of a single compound

Narrow melting point range

Pure sample of a single compound

What is the visual indicator that enough of a drying agent, such as anhydrous MgS04 or CaCl2, has been added to properly dry an organic solution?

The drying agent will move freely like a powder around the solution.

Identify the best practices when storing and using drying agents in the lab.

1. Wrap the lid of the drying agent container with tape for storage.

2. Close the drying agent container whenever it is not in active use.

Safety: 3,4-DICHLORONITROBENZENE is a

Toxic irritant

Safety: Sodium Methoxide

Flammable and corrosive

Safety: Methanol

Flammable and toxic

Safety: Dichloromethane

Toxic irriant

Safety: Magnesium Sulfate

Irritant

Structure for 3, 4-dichloronitrobenzene