Efficient and rapid synthesis of phenolic analogs of 4-phenylbutanoic acid using microwave-assisted Michael addition as a key reaction

ABSTRACT

The addition of phenols to acrylonitrile in the presence of aqueous benzyltrimethylammonium hydroxide or tetramethylammonium hydroxide under microwave irradiation yielded the corresponding Michael adducts. The obtained adducts were easily transformed to phenolic analogs of 4-phenylbutanoic acids via the hydrolysis of nitrile groups.

GRAPHICAL ABSTRACT

Keywords:

• Michael addition
• microwave irradiation
• 4-PBA

Acknowledgments

This work was financially supported by the Institute of Science and Technology, Kanto Gakuin University, in 2013. The authors are grateful to MEXT, Japan, for purchasing the high-field NMR instrument (JNM-ECX500II) with the Matching Fund Subsidy for Private Universities (to H. I. as a representative in 2013). H. I. extends his gratitude to Sasakawa Scientific Research (Grants No. 6-182 and No. 7-199 K) and Sasakawa Grants for Science Fellows (No. F02-109) from the Japan Science Society for supporting his research.