Concise and Practical Total Synthesis of (+)-Abscisic Acid

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Abscisic acid is a crucial plant hormone regulating various growth and developmental processes.
• Efficient and stereoselective synthesis of abscisic acid is important for research and agricultural applications.

Purpose of the Study:

• To develop a concise and efficient total synthesis of (+)-Abscisic acid.
• To establish the Z-configuration of abscisic acid through stereoselective chemical transformations.

Main Methods:

• The synthesis started from ethyl 2,6,6-trimethyl-4-oxocyclohex-2-ene-1-carboxylate.
• Key steps included Sharpless asymmetric epoxidation for stereoselective hydroxyl group introduction.
• Side chain attachment using dimethyl 2-(propan-2-ylidene)malonate followed by selective decarboxylation.

Main Results:

• The total synthesis of (+)-Abscisic acid was accomplished in seven steps.
• An overall yield of 41% was achieved for the target molecule.
• The Z-configuration of the conjugated acid was successfully established.

Conclusions:

• A practical and concise synthetic route to (+)-Abscisic acid has been developed.
• The methodology allows for stereoselective control crucial for synthesizing plant hormones.
• This synthesis provides a valuable method for accessing abscisic acid and its analogs.