Described are methods of forming protected boronic acids that provide in a manner that is straightforward, scalable, and cost-effective a wide variety of building blocks, such as building blocks containing complex and/or pharmaceutically important structures, and/or provide simple or complex protected organoboronic acid building blocks. A first method includes reacting an imino-di-carboxylic acid and an organoboronate salt. A second method includes reacting a N-substituted morpholine dione and an organoboronic acid.