245 research outputs found
A route to benzodithiophene systems by exploiting a ligand-free Suzuki-Miyaura coupling reaction in deep eutectic solvents
Benzo[1,2-b:4,3-b\u2019]dithiophene (BDT) and its derivatives belong to an interesting class of thiophene-based aromatic \uf070-conjugated compounds that are widely studied as functional organic materials inserted, for instance, as units in mono and polydisperse oligomers [1], or as \uf070-spacers in push-pull organic chromophores for photovoltaic applications [2]. Moreover, BDTs are key intermediates for the synthesis of inherent chiral tetrathia[7]helicenes, which are an attractive class of heterohelicenes with unique physicochemical and chiroptical properties due to their helix-like structure [3]. Thus, BDT is a key starting molecule which can allow access to more complex and interesting systems through a selective and judicious functionalization of the \uf061 and \uf062-positions of the terminal thiophene rings. Building on our recent studies on the synthesis and functionalization of BDTs [4], we questioned whether a novel class of 2,7-diarylsubstituted BDTs 1 (Figure 1) could be synthesized via a palladium-catalysed Suzuki-Miyaura reaction between heteroaryl halides 2 and organoboron derivatives 3 in Deep Eutectic Solvents (DESs), which have proven to be effective as sustainable and environmentally responsible reaction media in several transition-metal-catalyzed reactions [5].In this communication, we report our preliminary results on the preparation of diarylsubstituted BDTs 1, and discuss the substrate scope of the proposed protocol. Some of the compounds so far obtained display interesting photophysical properties, which are currently under investigation
A Fast and General Route to Ketones from Amides and Organolithium Compounds under Aerobic Conditions: Synthetic and Mechanistic Aspects
Paediatric Home Artificial Nutrition in Italy: Report from 2016 Survey on Behalf of Artificial Nutrition Network of Italian Society for Gastroenterology, Hepatology and Nutrition (SIGENP)
Home Artificial Nutrition (HAN) is a safe and efficacious technique that insures children's reintegration into the family, society and school. Epidemiological data on paediatric HAN in Italy are not available. Aim: to detect the prevalence and incidence of Home Parenteral Nutrition (HPN) and Home Enteral Nutrition (HEN), either via tube or mouth, in Italy in 2016. Materials and methods: a specific form was sent to all registered SIGENP members and investigators of local HAN centres, inviting them to provide the requested centre's data and demographics, underlying diseases and HAN characteristics of the patients. Results: we recorded 3403 Italian patients on HAN aged 0 to 19 years from 22 centres: 2277 HEN, 950 Oral Nutritional Supplements (ONS) and 179 HPN programs. The prevalence of HEN (205 pts/million inhabitants) and HPN (16 pts/million inhabitants) has dramatically increased in Italy in the last 9 years. Neurodisabling conditions were the first indication for HEN by tube or mouth while HPN is mainly requested in digestive disorders. Conclusions: HAN is a widespread and rapidly growing treatment in Italy, as well as in other European countries. Awareness of its extent and characteristics helps improving HAN service and patients' quality of life
Modern Lithium Carbenoid Chemistry (Chapter 11)
This chapter addresses the reactivity of a-lithiated organohalogens, ethers, and amines. Special emphasis is placed on their structure, configurational stability, and applications to synthetic chemistry in light of the recent advances that have appeared in the literature over the past decade. The chapter highlights the role played by aggregation and solvation on the structure-reactivity relationship. The characteristic features of a-lithiated halogens (Li/Hal) and a-lithiated ethers (Li/OR) carbenoids are discussed. These include: (i) the electrophilic reactivity, as observed in reactions with nucleophiles; (ii) the deshielding of the C atom in the NMR spectrum; and (iii) the C-X bond length in the corresponding solid state structures. The chapter concludes with a discussion on lithium-nitrogen carbenoids
Finding Joy with Lithium Chemistry: From Application in Medicine to Stereoselective Synthesis Through Tailored Self-Assembly
Polar organometallic chemistry meets deep eutectic solvents in flow
Polar organometallic chemistry in water and deep eutectic solvents (DESs) have recently captured the attention of chemists. In this issue of Chem, Torrente-Murciano, Hevia, and co-workers pioneer the first continuous and safe handling of organometallic reagents in (aqueous) DESs with an easy setup and without clogging problems at room temperature
The Quest for New Chiral and Configurationally Stable Lithium Carbenoids for Asymmetric Synthesis
GIORNATE SCIENTIFICHE DEL CONSORZIO CINMPIS 2023
Last February 2023, the XXI Edition of CINMPIS Days, organized by the Chemistry and Industrial Chemistry Department of the University of Pisa, took place in Pisa. This is a traditional event that takes place each year aimed at disseminating the scientific activities of the 13 italian universities belonging to CINMPIS Consortium, with several Invited Lectures representatives of both academia and industry
The Beauty of Reactive Intermediates. Aziridinyl- and Oxiranyllithiums: Structure, Dynamics and Reactivity – Cerimonia di Conferimento del Sigillo d’Oro dell’Università di Bari al Prof. Jean-Marie Pierre Lehn, Bari, 23 settembre 2008
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