5,10,15,20-Tetrakis(4-hydroxyphenyl) porphyrin (THPP) is a synthetic porphyrin compound that belongs to the group of meso tetraarylporphyrins.The compound has strong absorption in the visible region, which gives it an intense color typical of porphyrin molecules.It has a ring made of four pyrrole units connected by methine -CH= bridges, a very mobile electronic system, these properties are very important in the adsorption process of these compounds on diverse metals surfaces and four phenyl rings attached at the meso positions.Because of its structure, THPP dissolves in organic solution, the yield of porphyrins in condensation reaction decreases if there is water in the reaction medium.