Regioselective Photocycloaddition of Saccharin. Continuous Flow Synthesis of Benzosultams and Theoretical Study

GABRIELA OKSDATH-MANSILLA; FRANCISCO N. FIGUEROA; JUAN E. ARGUELLO; DIEGO SAMPEDRO

Koln

Simposio; 20th European Symposium on Organic Chemistry (ESOC 2017); 2017

Benzosultams are heterocyclic sulfonamide compounds which are importantpharmaceuticals with a broad spectrum of biological activities. In particular, saccharinsalready have the sulfonamide functionality in the heterocyclic system and it has beenshown diverse biological activities. In addition, ring-expanded saccharin derivative suchas oxicams is used as an anti-inflammatory drug.[1]Due to the biological importance of benzosultams, the development of differentsynthetic approach is of great interest to organic and medicinal chemists. In thiscontext, synthetic organic photochemistry constitutes a research area which could beobtained natural products as well as molecules with high structural complexity, in asimple and efficient way.In particular, there are few reports about photochemistry saccharins study withsynthetic application. [2] Recently, in our group photocyclizations of N-(thioalkyl)-saccharins were carried out obtaining different polycyclic sultams in good yields. Theseresults motivate us to continue exploring photo-reactivity of saccharin with syntheticapplications.[3]Taking into account the similitude of saccharin with phthalimide and in fact tophthalimides derivative can be participated in different photoreactions and used it in thesynthesis of heterocyclic compounds with new rings; we decide carried out thephotocycloaddition of saccharin with -methyl-styrene to evaluated the best conditionto obtaining benzosultam 1Additionally, we report a photocycloaddition study of saccharin anion with differentelectron-rich systems. We evaluated the benzosultams photo-generation in flow systemand theoretical studies were developed by way of decide the regioselectivity observed.Literature:[1] Majundar, K. C; Mondal S. Chem. Rev., 2011, 111, 7749-7773. [2] (a) Döpp, D. Intr.J. Photochem. 2001, 3, 41-48. (b) Cho, D. W.; Oh, S. W.; Kim, D. U.; Park, H. J.; Xue,J. Y.; Yoon, U. C.; Mariano, P. S. Bull. Korean Chem. Soc. 2010, 31, 2453-2458. [3]Castro-Godoy, W.; Oksdath-Mansilla, G.;* Argúello, J. E.;* Peñéñory, A. B.l J. Org.Chem. 2017, 82, 101-108.