Substituted and annulated pyrroles containing chiral centers are potentially accessible by means of an organocatalytic enantioselective Friedel-Crafts alkylation (FCA) reaction. They are interesting compounds because of their abundant natural occurrence and their different biological activities. In comparison to indoles, for which a myriad of asymmetric procedures involving the FCA have been developed, pyrroles have been relatively less used as nucleophilic counterparts in this reaction. However, in the last two decades, huge synthetic efforts have been performed around this interesting asymmetric transformation and several methodologies have been devised. In this context, this review article provides a general overview of the organocatalytic enantioselective FCA chemistry of pyrroles, which has not been revised to date. Reactions 2.4. Brønsted Acid Catalyzed Intramolecular FCA Reactions 3.Organocatalytic FCA Reactions with Dihydroindoles 4.Conclusions and Outlook

The asymmetric intramolecular aza-Michael reaction (IMAMR) is a very convenient strategy for the generation of heterocycles bearing nitrogen-substituted stereocenters. Due to the ubiquitous presence of these skeletons in natural products, the IMAMR has found widespread applications in the total synthesis of alkaloids and biologically relevant compounds. The development of asymmetric versions of the IMAMR are quite recent, most of them reported in this century. The fundamental advances in this field involve the use of organocatalysts. Chiral imidazolidinones, diaryl prolinol derivatives, Cinchone-derived primary amines and quaternary ammonium salts, and BINOL-derived phosphoric acids account for the success of those methodologies. Moreover, the use of N-sulfinyl imines with a dual role, as nitrogen nucleophiles and as chiral auxiliaries, appeared as a versatile mode of performing the asymmetric IMAMR.

An organocatalytic desymmetrizing IMAMR with vinyl sulfonamides as nitrogen nucleophiles has been devised with good levels of diastereo- and enantioselectivity.

A novel strategy for the synthesis of policyclic trifluoromethyl arenes has been devised. It involves a DBU-promoted tandem cycloaromatization reaction of dicyanoalkenes and fluorinated conjugated sulfinyl imines. This unprecedented transformation...

The interest in 3,4-dihydropyrimidine-2(1H)-(thio)ones is increasing every day, mainly due to their paramount biological relevance. The Biginelli reaction is the classical approach to reaching these scaffolds, although the product diversity suffers from some limitations. In order to overcome these restrictions, two main approaches have been devised. The first one involves the modification of the conventional components of the Biginelli reaction and the second one refers to the postmodification of the Biginelli products. Both strategies have been extensively revised in this manuscript. Regarding the first one, initially, the modification of one of the components was covered. Although examples of modifications of the three of them were described, by far the modification of the keto ester counterpart was the most popular approach, and a wide variety of different enolizable carbonylic compounds were used; moreover, changes in two or the three components were also described, broadening the substitution of the final dihydropyrimidines. Together with these modifications, the use of Biginelli adducts as a starting point for further modification was also a very useful strategy to decorate the final heterocyclic structure.