Abstract: A microarray and a process for making the microarray having a library of chemical compounds are disclosed herein. Each member of the library is attached at a known location. The microarray has a plurality of addressable electrodes and a porous reaction layer attached to each electrode. The porous reaction layer has reactive hydroxyl groups. Michael acceptors are attached to the porous reaction layer of selected electrodes. The Michael acceptors are attached at the hydroxyl groups using electrochemically-generated base that is generated by the selected electrodes and confined to the selected electrodes with the use of excess activated ester. At least one of a plurality of chemical compounds from a library of compounds is attached to the olefin of the plurality of Michael acceptors. Attachment occurs only at the selected electrodes having Michael acceptors with unreacted olefin. Each member of the library of compounds is attached to the known locations.