We report herein the efficiency of quaternary ammonium salts as co-catalysts in organocatalytic Michael reactions involving iminium activation of α,β-unsaturated aldehydes. The enantioselective formal benzylation of these substrates has been optimized and used to rationalize the role of the ammonium salts in these processes.

When otologic procedures that involve tympanic membrane repairs are performed, biomaterials or biological tissues as normal as grafts are used. At the moment, biological material from the own patient is used with varying success rates. The procedure used and the patient's tissue repair capabilities tend to determine the outcome. We present a preliminary study on tympanic membrane perforation repairs using an autograft obtained by manipulating platelet degranulation and the coagulation cascade and reinforced with a seal using platelet growth factors. We present three cases in which we used this procedure. The results will be valued based on the tympanic perforation closure index. With this study, we want to assess the effectiveness of tympanic perforation repairs with this technically simple method. If this method was objectively proved to be effective, it would lead to lower patient morbidity and sanitary costs.

14 Nyhus LM. The preperitoneal approach and iliopubic tract repair of all groin hernias. In: Nyhus LM, Harkins HN, cds. Hernia. Philadelphia, Pennsylvania: JB Lippincott, 1%4: 271-314. I5 Parry E. The influence of rotation of the trunk on the anatomy of the inguinal canal. Er J Surg 1966, 53: 205-10. 16 Gullmo A, Broom6 A, Smedberg S.

Enantioselective Organocatalytic β-Benzylation of Enals. -The ammonium salt supports the formation and stabilization of the iminium intermediate and, additionally, activates the nucleophile as an enolate. -(DUCE, S.; MATEO, A.; ALONSO, I.; GARCIA RUANO*, J. L.; CID, M. B.; Chem. Commun. (Cambridge) 48 (2012) 42, 5184-5186, http://dx.