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Indole ring is widely represented in natural compounds, as well as in a great variety of drugs. In this paper, the synthesis of a 5-hydroxybenzoindole derivative carrying a pyridyl substituent on position 1 is reported. The method involved no chromatography for purification and used solvents and catalysts of very low toxicity. [ABSTRACT FROM AUTHOR]

This paper reports a new sustainable protocol for the microwave‐assisted catalytic conversion of levulinic acid into N‐substituted pyrrolidones over tailor‐made mono (Pd, Au) or bimetallic (PdAu) catalysts supported on either highly mesoporous silica (HMS) or titania‐doped HMS, exploiting the advantages of dielectric heating. MW‐assisted reductive aminations of levulinic acid with several amines were first optimized in batch mode under hydrogen pressure (5 bar) in solvent‐free conditions. Good‐to‐excellent yields were recorded at 150 °C in 90 min over the PdTiHMS and PdAuTiHMS, that proved recyclable and almost completely stable after six reaction cycles. Aiming to scale‐up this protocol, a MW‐assisted flow reactor was used in combination with different green solvents. Cyclopentyl methyl ether (CPME) provided a 99 % yield of N‐(4‐methoxyphenyl) pyrrolidin‐2‐one at 150 °C over PdTiHMS. The described MW‐assisted flow synthesis proves to be a safe procedure suitable for further industrial applications, while averting the use of toxic organic solvents. [ABSTRACT FROM AUTHOR]

Aryl and heteroaryl iodides have been efficiently converted into the corresponding thioacetates in cyclopentyl methyl ether (CPME), a green solvent, under Cu catalysis. The chemoselectivity of the reaction is mainly controlled by electronic factors, enabling the conversion of both electron-rich and electron-deficient substrates into the corresponding thioacetates in good to excellent yields. The products can be easily deprotected to the corresponding thiolates to carry out additional synthetic transformations in situ. Surprisingly, despite CPME's relatively low dielectric constant, the reaction rate significantly increased when conducted under microwave irradiation conditions. This synthetic methodology exhibits a remarkable tolerance to functional groups, mild reaction conditions, and a wide substrate scope, utilizing a safe and inexpensive CuI pre-catalyst in the green solvent CPME. A non-aqueous workup allowing for the complete recovery of both catalyst and solvent makes this approach an environmentally sustainable protocol for C(sp2) sulfur functionalization. Additionally, the reaction shows selective cross-coupling with iodides in competition with chlorides and bromides, allowing its use in multistep syntheses. To demonstrate the potential of this methodology, it was applied to the high-yield synthesis of a photochromic dithienylethene, where a selective synthesis had not been reported before. [ABSTRACT FROM AUTHOR]

Indole ring is widely represented in natural compounds, as well as in a great variety of drugs. In this paper, the synthesis of a 5-hydroxybenzoindole derivative carrying a pyridyl substituent on position 1 is reported. The method involved no chromatography for purification and used solvents and catalysts of very low toxicity.

A new, improved 2nd generation route for the synthesis of 3‐ethyl‐4‐hydroxy‐5‐methylbenzonitrile has been developed. The original route started from 2‐ethyl‐6‐methylaniline, which was converted by a classical sequence of para‐bromination, cyanation and Sandmeyer hydroxylation into the desired phenol. This route was used on multi‐kg scale and delivered the product with the desired purity. However, the route was not ideal, as it featured safety critical steps (cyanation), employed undesirable solvents (DMF), included laborious workup and isolation procedures, and suffered from a low overall yield (40–45 %) and suboptimal green metrics (PMI: 210). We envisioned a new, non‐classical approach to the product by introducing the nitrile through a para‐selective formylation, followed by transformation of the intermediate aldehyde into the nitrile with hydroxylamine‐O‐sulfonic acid (HOSA). The new sequence of Sandmeyer hydroxylation, Duff formylation and HOSA‐promoted nitrile formation was thoroughly optimized and finally scaled up to 400 g. This novel 3‐step sequence delivered 3‐ethyl‐4‐hydroxy‐5‐methylbenzonitrile in 69 % overall yield with excellent purity (99.3 % a/a) and a vastly improved PMI of 81. [ABSTRACT FROM AUTHOR]

Reaction of glycerol with aldehydes and ketones is a strategy widely studied in literature to valorize this bioproduct. A Brønsted or Lewis acid is normally used to activate the carbonyl function and various strategies adopted to drive the equilibrium to the products. In this study ammonium salts as catalysts, and removal of water by azeotropic distillation of cyclopentyl methyl ether, permit the conversion of glycerol into acetals obtained as mixture of dioxanes and dioxolanes determined by 1H‐NMR. Under the optimized conditions, the products could be obtained in excellent yield without using excess of reactants and the solvent was recycled efficiently. [ABSTRACT FROM AUTHOR]

Aryl and heteroaryl iodides have been efficiently converted into the corresponding thioacetates in cyclopentyl methyl ether (CPME), a green solvent, under Cu catalysis. The chemoselectivity of the reaction is mainly controlled by electronic factors, enabling the conversion of both electron-rich and electron-deficient substrates into the corresponding thioacetates in good to excellent yields. The products can be easily deprotected to the corresponding thiolates to carry out additional synthetic transformations in situ. Surprisingly, despite CPME’s relatively low dielectric constant, the reaction rate significantly increased when conducted under microwave irradiation conditions. This synthetic methodology exhibits a remarkable tolerance to functional groups, mild reaction conditions, and a wide substrate scope, utilizing a safe and inexpensive CuI pre-catalyst in the green solvent CPME. A non-aqueous workup allowing for the complete recovery of both catalyst and solvent makes this approach an environmentally sustainable protocol for C(sp2) sulfur functionalization. Additionally, the reaction shows selective cross-coupling with iodides in competition with chlorides and bromides, allowing its use in multistep syntheses. To demonstrate the potential of this methodology, it was applied to the high-yield synthesis of a photochromic dithienylethene, where a selective synthesis had not been reported before.

A general catalytic protocol for the Pd‐catalyzed intramolecular arylations of N‐(2‐halogenoaryl) amides in eco‐friendly medium was successfully developed by using rationally designed acenaphthoimidazolylidene‐ligated chiral oxazoline palladacycles. Under the optimal reaction condition, a broad scope of substrates with various functional groups were well tolerated, leading to desired 3,3′‐disubstituted oxindoles in excellent yields (up to 98% yield). [ABSTRACT FROM AUTHOR]

Though foot and ankle surgery fellowships have been around for decades, contributing factors for long-term research productivity remain unreported. Along with enhancing surgical training, the American College of Foot and Ankle Surgeons (ACFAS) tasked programs with fostering research in effort to continue post-fellowship investigations. As the number of fellowship programs and fellows continues to increase, this study attempts to identifies factors associated with postfellowship research success. A PubMed search of peer-reviewed literature authored by ACFAS recognized 1-year fellowship graduates from 2000-2018 was conducted. Demographic data including current practice type and location was collected. Research activity at the 3, 5, and 10-year postfellowship period was investigated between publication history and current practice type. Statistical significance was set at p ≤.05. Among the 37 fellowships assessed, 132 fellows were eligible for analysis. Most fellows maintained hospital-based employment 46 (34%) followed by private 44 (33%) and orthopedic group 30 (22%) practices. The proportion of fellows that published 5 and 10 years postfellowship was associated with research productivity 3 and 5 years postfellowship (p ≤.03). The odds of publishing 3 years post-fellowship in orthopedic groups and university-based practices were 1.62 and 4.42 times higher compared to hospital-based graduates, respectively. The odds of publishing 5 years post-fellowship in orthopedic group and university based practices were 3.5 and 6.63 times higher than hospital-based practices, respectively. Despite the growing number of fellowships, a small proportion of fellows continue publishing postfellowship. These findings support the need to provide resources to engage graduates if retaining young practitioners in scholarly activity is desired. [ABSTRACT FROM AUTHOR]

In this work, a novel capsule phase microextraction (CPME) method coupled to high performance liquid chromatography with diode array detection (HPLC-DAD) was developed and validated for the determination of coumarin in bakery products, in accordance with the European Commission Regulation (EC) 1334/2008. The CPME extraction protocol was optimized after examining the following critical parameters: a) selection of the CPME membrane, b) sample loading time c) type of elution solvent, and d) desorption time. The optimum extraction parameters involved the use of a sol-gel CPME capsule (1 cm length), 1 mL of sample loading volume, elution with 3 mL of methanol, the stirring was set at 350 rpm, while the absorption time was 20 min and the desorption time was 15 min. The developed CPME-HPLC-DAD method was validated in terms of selectivity, linearity, accuracy, and precision and showed satisfactory results. The LOD and LOQ were equal to 0.18 µg/g and 0.48 µg/g, respectively. Trueness was assessed by means of relative percentage of recovery and ranged between 83 to 91% for intra-day experiments, and between 81-86% for inter-day experiments, respectively. The green character of the proposed method was examined using complexGAPI index. The method was successfully applied in the analysis of coumarin in bakery products.

In this work, mild Lewis acids and low environmental impact solvents were investigated for Nenitzescu synthesis. Cyclopentyl methyl ether can be used at room temperature in substitution of halogenated solvents with zinc, iron and magnesium salts as homogeneous catalysts to give 5‐hydroxyindoles in fair to good yields. The reaction features a straightforward workup and excellent solvent recycle. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oil extraction from sewage sludge was studied using two methods for biodiesel production. • The efficiency of both organic and green solvents in oil extraction methods was examined. • Response surface methodology (RSM) was employed to model and optimize the oil extraction process. • Folch method using CPME solvent is a more efficient way for oil extraction from sewage sludge. • Biodiesel was produced using the NaOH/Clinoptilolite-Fe 3 O 4 catalyst via the electrolysis method. A comparative study of oil extraction from secondary dry sludge was performed via Reflux and Folch methods by cyclopentyl methyl ether (CPME) and hexane as green and organic solvents, respectively. Response surface methodology based on Box-Behnken design (RSM-BBD) was utilized to optimize and predict the impact of influential factors, including sludge amount (4–6 g), the volume of solvent (12–16 mL), and extraction time (2–6 h). The maximum oil extraction efficiency was 8.078 % and 4.076 % under the optimal conditions: 5.15 g, 16 mL, 2 h for CPME, and 4.22 g, 11 mL, 2 h for hexane. The raw sludge was characterized by FESEM and XRF analyses, while the extracted oil characteristics were determined by GC-Mass and FTIR methods. As a result, the Folch method by CPME solvent was a more efficient way to extract oil from sewage sludge. Finally, biodiesel was produced via the transesterification double-step process (TDSP) using NaOH/Clinoptilolite-Fe 3 O 4 magnetic catalyst. The production efficiency of biodiesel from the oil extracted by CPME and hexane is 6.94 % and 4.1 %, respectively. The maximum yield of biodiesel production was 6.94 % under the optimum reaction conditions: methanol to oil molar ratio of 10:1, catalyst weight of 0.45 wt%, and reaction time of 2.5 h with the help of the electrolysis method. [ABSTRACT FROM AUTHOR]