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Understanding the host-guest chemistry in MOFs represents a research field with outstanding potential to develop in a rational manner novel porous materials with improved performances in fields such as heterogeneous catalysis. Herein, we report a family of three isoreticular MOFs derived from amino acids and study the influence of the number and nature of functional groups decorating the channels as a catalyst in hemiketalization reactions. In particular, a multivariate (MTV) MOF 3, prepared by using equal percentages of amino acids L-serine and L-mecysteine, in comparison to single-component (“traditional”) MOFs, derived from either L-serine or L-mecysteine (MOFs 1 and 2), exhibits the most efficient catalytic conversions for the hemiketalization of different aldehydes and ketalization of cyclohexanone. On the basis of the experimental data reported, the good catalytic performance of MTV-MOF 3 is attributed to the intrinsic heterogeneity of MTV-MOFs. These results highlight the potential of MTV-MOFs as strong candidates to mimic natural nonacidic enzymes, such as glycosidases, and to unveil novel catalytic mechanisms not so easily accessible with other microporous materials.

[EN] The exact chemical structure of non-crystallising natural products is still one of the main challenges in Natural Sciences. Despite tremendous advances in total synthesis, the absolute structural determination of a myriad of natural products with very sensitive chemical functionalities remains undone. Here, we show that a metal-organic framework (MOF) with alcohol-containing arms and adsorbed water, enables selective hydrolysis of glycosyl bonds, supramolecular order with the so-formed chiral fragments and absolute determination of the organic structure by single-crystal X-ray crystallography in a single operation. This combined strategy based on a biomimetic, cheap, robust and multigram available solid catalyst opens the door to determine the absolute configuration of ketal compounds regardless degradation sensitiveness, and also to design extremely-mild metal-free solid-catalysed processes without formal acid protons. Elucidation of the chemical structure of natural products constitutes one of the main challenges in Natural Sciences. Here, the authors show that an amino acid-based metal-organic framework exhibits hydrolase-like catalytic activity and crystallographic determination of the resulting products

Prendendo come spunto una monografia del sociologo ed epistemologo Davide Sparti, dal titolo "Suoni inauditi", l'autrice si interroga sulla possibilità di usare la metafora della musica jazz, e dell'improvvisazione che la caratterizza, per parlare del lavoro autobiografico in educazione. La risposta è positiva, se si intende l'autobiografia come il partecipare a una con-versazione nella quale si com-pone un'identità provvisoria, costruita sul filo del raccontarsi e dell'ascoltarsi/influenzarsi reciproco.