(E)-3-[4-(Pent-4-en-1-yloxy)phenyl]acrylicc Acid

(E)-3-[4-(Pent-4-en-1-yloxy)phenyl]acetic acid is one of the useful components of liquid crystal materials which can be produced through Williamson ether synthesis by synthesizing 4-hydroxy-cinnamic acid and 5-bromo-1-pentene. Although Williamson ether synthesis is generally slow under conventional external heating conditions, microwave irradiation was effective for significant acceleration of the etherification. Furthermore, we demonstrated the rapid and continuous synthesis of (E)-3-[4-(pent-4-en-1-yloxy)phenyl]acetic acid, using a microwave-assisted flow reactor developed by us, in which the blockage by salt precipitation was suppressed by the continuous addition of an aqueous methanol solution after the reaction cavity.