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The reaction between γ-azido-N-tosylhydrazones and boronic acids leads to the obtention of 2,2-disubstituted pyrrolidines in a domino process that includes 1) diazoalkane formation, 2) intermolecular carboborylation of the diazocompound, and 3) intramolecular carborylation of the azide, and comprises the formation of a Csp3 -Csp3 and a Csp3 -N bonds on the same carbon atom. The reaction proceeds without the need of any transition-metal catalyst under microwave activation and features wide scope in both reaction partners. It can be applied to both alkyl and arylboronic acids with equal efficiency. With N-tosylhydrazones derived from 2-(2-azidoethyl)-cyclopentanone and cyclohexanone the reactions are highly diastereoselective leading to the cis-fused bicyclic systems as unique diastereoisomers. The scope of the process is illustrated by over sixty examples, including scaffolds present in natural alkaloids, and the mechanistic proposal is suppported by DFT-based computations.

The establishment of emotional bonds is one of the most important tasks of the adoptive family. Most research about attachment in adoption focuses on young adopted children, as opposed to adoptees in other stages of development. The present study aims at assessing the adopted adolescents' self-perception of attachment relationships with their adoptive parents, by pairing them with a group of institutionalized adolescents and another one of adolescents in the community. One hundred sixty-five adolescents (55 adopted, 55 in residential care, and 55 living with their birth family), aged 12 to 19, participated in this study. Data were collected using the Inventory of Parent and Peer Attachment to assess attachment relationships with parents on three dimensions: trust, communication, and alienation. The results showed that adoptees perceived their relationship with their parents in a similar way to peers in the community and presented higher results when compared to institutionalized adolescents in trust and communication and lower scores in alienation. The results highlighted the relevance of family context experiences and suggested that adoption can offer the possibility of building a secure attachment relationship, which is not the case in the context of collective care, as happens within institutionalized care.

A very straightforward diastereoselective synthesis of tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular 1,3-dipolar cycloaddition is described. The starting materials for the synthetic route are N-Boc-protected α-amino acids, which are first transformed into N-allyl-α-amino ketones through conventional methodologies. Then, a one-pot sequence that involves formation of a tosylhydrazone from the ketone, base-induced decomposition of the hydrazone, and intramolecular 1,3-dipolar cycloaddition of the diazo compound generated, gives rise to the bicyclic systems with total diastereoselectivity and high preservation of the enantiomeric purity. However, the analogous process employing α-amino aldehydes lacks stereoselectivity. DFT computational modeling has been carried out to account for the different behavior of the two types of systems.

1,3-Diaryl-3-trifluoromethylcyclopropenes and 2-aryl- or 2-alkyl-1,3-diaryl-3-trifluoromethylcyclopropenes are prepared in a very simple way by reaction between 1,1,1-trifluoroacetophenone tosylhydrazones and terminal or internal alkynes, respectively, in a base promoted process that does not require the presence of any metal catalyst. The essential role of the trifluoromethyl group, which enables the formation of the cyclopropenes instead of the expected pyrazoles, has been computationally investigated, suggesting the participation of a free carbene.

The Pd-catalyzed reaction between 2,2'-dibromobiphenyls and related systems with tosylhydrazones gives rise to new π-extended conjugated polycarbo- and heterocycles through an autotandem process involving a cross-coupling reaction followed by an intramolecular Heck cyclization. The reaction shows wide scope regarding both coupling partners. Cyclic and acyclic tosylhydrazones can participate in the process. Additionally, a variety of aromatic and heteroaromatic dibromoderivatives have been employed, leading to an array of diverse scaffolds featuring a fluorene or acridine central nucleus, and containing binaphthyl, thiophene, benzothiophene and indole moieties. The application to appropriate tetrabrominated systems led to greater structural complexity through two consecutive autotandem cascades. The photophysical properties of selected compounds were studied through their absorption and emission spectra. Fluorescence molecules featuring very high quantum yields were identified, showing the potential of this methodology in the development of molecules with interesting optoelectronic properties.

A very straightforward diastereoselective synthesis of tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular 1,3-dipolar cycloaddition is described. The starting materials for the synthetic route are N-Boc-protected α-amino acids, which are first transformed into N-allyl-α-amino ketones through conventional methodologies. Then, a one-pot sequence that involves formation of a tosylhydrazone from the ketone, base-induced decomposition of the hydrazone, and intramolecular 1,3-dipolar cycloaddition of the diazo compound generated, gives rise to the bicyclic systems with total diastereoselectivity and high preservation of the enantiomeric purity. However, the analogous process employing α-amino aldehydes lacks stereoselectivity. DFT computational modeling has been carried out to account for the different behavior of the two types of systems.

The reaction of tosylhydrazones of cyclic ketones and 2,2′-dibromobiphenyls involves cross-coupling with tosylhydrazone followed by an intramolecular Heck reaction giving various spirocyclic structures.