Q65. - Organic Chemistry

Question

Question: Devise a synthesis of anastrozole, a drug used to reduce the recurrence of breast cancer (Section 22.18), from the given compounds. You may use any other needed organic compounds or inorganic reagents.

Step-by-Step Solution

Answer

Answer

Step 1: Conversion of the alkyl halide to alkyl cyanide

The reaction of an alkyl halide with a cyanide salt (such as NaCN or KCN) leads to the replacement of the halide group with the cyanide group.

Step 2: Synthesis of anastrozole

The synthesis of anastrozole is shown below.

• The reaction of alkyl bromide with KCN (cyanide salt) yields alkyl cyanide.
• The reaction of this compound with methyl iodide in the presence of a strong base leads to the substitution of the methyl groups on the carbon connected to the cyanide group.
• A bromine atom gets substituted on the methyl group connected to the benzene ring on treatment with N-bromosuccinimide (in the presence of a peroxide).
• The final step involves the reaction of the obtained compound with 1H-1,2,3-triazole in the presence of a base yielding anastrozole.

                       Synthesis of anastrozole