Reacciones tipo click para la síntesis de esteres y amidas de manera más sosteniblea partir de derivados de la ciclopropenona

[ES] La cicloadición 1,3-dipolar entre alquinos y azidas ("Click Chemistry") catalizada por cobre (I), para formar 1,2,3-triazoles, es una de las reacciones más populares debido a su fiabilidad, especificidad y biocompatibilidad. Este tipo de mecanismos tienen el potencial de acortar los procedimientos y optimizarlos consiguiendo una economía atómica del 100%, además tienen la posibilidad de llevar a cabo la reacción en distintas condiciones y en un gran número de disolventes distintos, incluyendo el agua. Esta combinación de factores hace que las reacciones tipo "click" sean de gran utilidad para el diseño y la síntesis de una gran variedad de compuestos en condiciones óptimas de reacción. Un gran avance sería el descubrimiento de una reacción tipo "click" para amidas y esteres, que son compuestos químicos que se encuentran tanto en la naturaleza como en los laboratorios y de los cuales se conocen numerosos métodos sintéticos, sin embargo, estos no suelen ser sostenibles y generalmente requieren de reactivos peligrosos y condiciones violentas de reacción. Por estos motivos, en este trabajo se ha propuesto la síntesis de esteres y amidas a partir de la apertura de anillo de derivados de la ciclopropenona en presencia de aminas y alcoholes según los mecanismos de "Click Chemistry", utilizando distintas condiciones de reacción (temperatura, disolventes, catalizadores, etc.).[EN] 1,3-dipolar cycloaddition between alkynes and azides catalyzed by copper (I) (click reaction), to form 1,2,3-triazoles, is one of the most popular reactions due to its reliability, specificity, and biocompatibility. Click reactions have the potential to perform shorter procedure and optimize them, achieving an atomic economy of 100%, and operate in different conditions and in many conventional solvents, including water. This combination of factors makes click reactions of great utility for the design and synthesis of a plethora compounds under optimal reaction conditions. A great advance would be the discovery of a click reaction for amides and esters synthesis, which are common chemicals in Nature, industry and academic laboratories. Indeed, a plethora of synthetic methods have been developed over the years, however, these methods are not sustainable and generally require harsh reagents or reaction conditions. For these reasons, in this work has been proposed the synthesis of esters and amides form the ring-opening of cyclopropenones derivatives in the presence of amines and alcohols according to the mechanisms of Click Chemistry.Palomar De Lucas, B. (2021). Reacciones tipo click para la síntesis de esteres y amidas de manera más sosteniblea partir de derivados de la ciclopropenona. Universitat Politècnica de València. http://hdl.handle.net/10251/175095TFG

Morphometric characterization of the human portal and hepatic venous trees: A quantitative support to the liver micro-anatomic models free of subunits

Conventional models of liver microanatomy assume the presence of subunits. Nevertheless, some researchers propose that the liver is a continuous structure, free of these subunits, but with a characteristic vascular pattern. The present study describes a morphometric analysis of portal and hepatic veins in 50 human autopsy non-pathological liver samples. The main objective was to measure three proportions: 1. portal tracts / hepatic veins, 2. distributing portal veins / distributing hepatic veins and 3. terminal portal veins / terminal hepatic veins. These ratios were compared with the traditional microcirculatory liver models. Our material comprised 3,665 portal veins and 3,761 hepatic veins. The minimum diameter of half of the venous vessels of both types belongs to the interval (25 μm , 60 μm), given that 1881 portal veins (49.434%) and 1924 hepatic veins (50.565%) fall within this interval. We have statistically shown with the χ2 test (α=0.990) that the portal and hepatic veins belonging to the interval (25 μm, 400 μm) (distributing veins) had an identical proportion. If the portal and hepatic veins are arranged according to the principle of interdigitation of Takashasi (1970), there should be an almost identical number of both types of veins. Our results contradict the presumably numeric preponderance of distributing portal veins with regard to the distributing hepatic veins that is inherent in the models of Kiernan, Matsumoto and Rappaport

Click amidations, esterifications and one-pot reactions catalyzed by Cu salts and multimetal-organic frameworks (M-MOFs)

Amides and esters are prevalent chemicals in Nature, industry and academic laboratories. Thus, it is not surprising that a plethora of synthetic methods for these compounds has been developed along the years. However, these methods are not 100% atom economical and generally require harsh reagents or reaction conditions. Here we show a 'spring-loaded', 100% atom-efficient amidation and esterification protocol which consists in the ring opening of cyclopropenones with amines or alcohols. Some alkyl amines react spontaneously at room temperature in a variety of solvents and reaction conditions, including water at different pHs, while other alkyl amines, aromatic amines and alcohols react in the presence of catalytic amounts of simple Cu2+ salts or solids. A modular reactivity pattern (alkyl amines >> alkyl alcohols >> phenols >> aromatic amines) enables to design orthogonal and one-pot reactions on well-defined catalytic Multimetal-Organic Frameworks (M-MOFs, M= Cu, Ni, Pd), to easily functionalize the resulting cinnamides and cinnamic esters to more complex molecules. The strong resemblance of the amidation and esterification reaction conditions here reported with the copper- catalyzed azide-alkyne cycloaddition (CuAAC) allows to define this fast, clean and flexible protocol as a click reaction

Functionalization of polyethylene with hydrolytically-stable ester groups

[EN] Low-density (LD) and high-density polyethylene (HDPE), recycled or not, incorporates up to 7 wt% of ester groups after reacting either with ethyl diazoacetate (EDA) under catalytic and solvent free-reaction conditions, or with maleic anhydride (MA) and acrylates (AC) under catalytic radical conditions. The resulting upcycled polyethylene esters are hydrolytically stable at extreme pH (0-14) and can be further transformed into carboxylic acids, carboxylates, other esters and amides.Financial support by the projects PID2020-115100GB-I00 and TED2021-130465B-I00 (funded by Spanish MCIINN, MCIN/AEI/10.13039/501100011033MICIIN) is acknowledged. The work has also been funded by Generalitat Valenciana, Grupos Emergentes (GV/2021/138). AIMPLAS author thanks Instituto Valenciano de Competitividad Empresarial (IVACE) the founding from the project IMAMCA/2023/4. AIMPLAS and ITQ authors thank Agencia Valenciana d'Innovacio (AVI) and the European Union the founding of the project INNEST/2022/18. J. O.-M. acknowledges the Juan de la Cierva program for the concession of a contract (IJC2018-036514-I). S. H.-A, and C. B. and P. M.-V. thank ITQ, UPV-CSIC for the concession of a contract (FPI-2022-S2-42040 and PAID 01-20, respectively).Hervàs-Arnandis, S.; Palomar-De Lucas, B.; Bilanin-Artigado, C.; Mingueza-Verdejo, P.; Viciano, M.; Oliver-Meseguer, J.; Leyva Perez, A. (2023). Functionalization of polyethylene with hydrolytically-stable ester groups. RSC Advances. 13(34):23859-23869. https://doi.org/10.1039/d3ra05024f2385923869133

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)