Divergent role of PIDA and PIFA in the AlX (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study.

The reaction mechanism for the chlorination and bromination of 2-naphthol with PIDA or PIFA and AlX (X = Cl, Br), previously reported by our group, was elucidated via quantum chemical calculations using density functional theory. The chlorination mechanism using PIFA and AlCl demonstrated a better experimental and theoretical yield compared to using PIDA. Additionally, the lowest-energy chlorinating species was characterized by an equilibrium of Cl-I(Ph)-OTFA-AlCl and [Cl-I(Ph)][OTFA-AlCl], rather than PhICl being the active species.

Discovery and Characterization of a Chemical Probe Targeting the Zinc-Finger Ubiquitin-Binding Domain of HDAC6.

Histone deacetylase 6 (HDAC6) inhibition is an attractive strategy for treating numerous cancers, and HDAC6 catalytic inhibitors are currently in clinical trials. The HDAC6 zinc-finger ubiquitin-binding domain (UBD) binds free C-terminal diglycine motifs of unanchored ubiquitin polymer chains and protein aggregates, playing an important role in autophagy and aggresome assembly. However, targeting this domain with small molecule antagonists remains an underdeveloped avenue of HDAC6-focused drug discovery.

Iodine(III) reagents for oxidative aromatic halogenation.

Iodine(III) reagents have attracted chemical relvance in organic synthesis by their use as safe, non-toxic, green and easy to handle reagents in different transformations. These characteristics make them important alternatives to procedures involving hazardous and harsh reaction conditions. Their versatility as oxidants has been exploited in the functionalization of different aromatic cores, which allow the introduction of several groups.

Iodine(III)-Catalyzed Electrophilic Nitration of Phenols via Non-Brønsted Acidic NO Generation.

The first catalytic procedure for the electrophilic nitration of phenols was developed using iodosylbenzene as an organocatalyst based on iodine(III) and aluminum nitrate as a nitro group source. This atom-economic protocol occurs under mild, non-Brønsted acidic and open-flask reaction conditions with a broad functional-group tolerance including several heterocycles. Density functional theory (DFT) calculations at the (SMD:MeCN)Mo8-HX/(LANLo8+f,6-311+G*) level indicated that the reaction proceeds through a cationic pathway that efficiently generates the NO ion, which is the nitrating species under neutral conditions.

Practical, mild and efficient electrophilic bromination of phenols by a new I(iii)-based reagent: the PIDA-AlBr system.

A practical electrophilic bromination procedure for phenols and phenol-ethers was developed under efficient and very mild reaction conditions. A broad scope of arenes was investigated, including the benzimidazole and carbazole core as well as analgesics such as naproxen and paracetamol. The new I(iii)-based brominating reagent PhIOAcBr is operationally easy to prepare by mixing PIDA and AlBr.