Sulfonic Acid Functionalized Silica: A Mild, Reusable and Efficient Heterogeneous Catalyst for the Highly Diastereoselective Synthesis of cis-Isoquinolonic Acids

摘要

Sulfonic acid functionalized silica (SAFS) is found to be a recyclable heterogeneous catalyst for the rapid and efficient synthesis of various cw-isoquinolonic acids from the three-component condensation reaction of homophthalic anhydride, an amine, and an aldehyde. This reaction was highly diastereoselective and only one diastereomer was obtained in all cases.Tetrahydroisoquinoline derivatives are an important class of natural and synthetic compounds, which have shown a wide range of biological and pharmacological activity.1 These compounds are useful for the treatment of glaucoma,2 migraine headache,2 and diseases of the central nervous system.3 They are also useful in the treatment of cardiovascular diseases, for example, hypertention, angina pectoris, arrhythmias, and obstruction of cardiac outflow.