A degree of hydrophobicity is necessary for organic structure-directing agents to form pure-silica zeolites. The ethanolalkylammonium cations described here have approximately the same size and shape as tetrapropylammonium and differ only by their ability to form hydrophilic hydrogen bonds in aqueous solution. The synthesis results show that TPA is a more effective SDA, as evidenced by the increased rate of crystallization and preferential occlusion within the intracrystalline space. While ethanoltripropylammonium is capable of directing the formation of pure-silica ZSM-5, diethanoldipropylammonium, alone, does not influence spontaneous nucleation. is shown to be a very effective tool for investigating occlusion of organic molecules, particularly when the synthesis solution contains a mixture of SDAs.