Q65E - Organic Chemistry (Mcmurry)

Question

The compound MON-0585 is a nontoxic, biodegradable larvicide that is highly selective against mosquito larvae. Synthesize MON-0585 using either benzene or phenol as a source of the aromatic rings.

Step-by-Step Solution

Answer

The synthesis of MON-0585 using benzene as a source of aromatic ring is shown below:

Step 1: Friedel-Crafts alkylation

Friedel craft Alkylation is an organic reaction refers to the replacement of an aromatic proton with an alkyl group. This is done through an electrophilic attack on the aromatic ring with the help of a carbocation. The Friedel-Craft alkylation reaction is also known as a method of generating alkylbenzenes by using alkyl halides as reactants.

The Friedel craft alkylation of benzene is shown below:

Step 2: Synthesis of MONO-0585 from benzene

The product we obtain is the substituted phenol, whose –OH group directs the orientation of the –C(CH₃)₃ groups. The precursor to MON-0585 is synthesized by a Friedel-Crafts alkylation of phenol by the appropriate hydrocarbon halide. This compound is synthesized by NBS bromination of the product of alkylation of benzene with 2-chloropropane.

Synthesis of MON-0585 using benzene as a source of aromatic ring