To provide an economic and inexpensive process for preparing boronic acid and borinic acid.
The process for preparing boronic acid of formula (I) and borinic acid of formula (II) [wherein substituents R1' to R5' are each independently H, an alkyl, F, a fluoroalkyl, an alkoxy, an amine, phenyl, an aryl, a heteroaryl or the like; and X, Y and Z are each independently a carbon, or XR3', YR2' and/or ZR1' are each independently a nitrogen, or both ZR3' and YR2' are each an oxygen, or both XR3' and YR2' are each N (alkyl) or N (SiMe3), or both XR3' and YR2' are each a sulfur] comprises a step wherein a chloroaromatic compound of formula (III) (wherein W', W" and W'" are each an alkoxy, F, Cl, Br, or the like) is allowed to react with a lithium metal and a boron compound in a solvent at from 100 to 80°C.
ERBES MICHAEL
FORSTINGER KLAUS
