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Cleaner Routes for Friedel-Crafts Acylation
Full text linkFriedel-Crafts acylation is among the most fundamental and useful reactions to yield aromatic ketones but it is one of the less acceptable in terms of unwanted polluting by-products or atom economy because of the overconsumption of catalyst which is used in stoichiometric quantities in the conventional process. This route is nevertheless widely used in the fine chemical industry.In recent years, awareness of the impact of industrial activities on the environment has led chemists to work on new chemical routes, less dangerous and more environmentally friendly.We considered here the acylation of a benzofurane derivative by an acyl chloride, as an intermediary step for a pharmaceutical product. In this study, one of the first alternatives was to replace conventional catalysts (FeCl3 or AlCl3), by reusable solid catalysts. Indeed, a wide variety of new solid catalysts, more efficient and less polluting, has now emerged (zeolites, ion-exchange resins…). In this work, these catalysts were first tested in “conventional” conditions, i.e., using an organic solvent (1,2-dichlorobenzene in our case), to determine the best one, in terms of reactivity, lifetime and reusability. The zeolite Y was found the most appropriate.However, the use of an organic solvent still remains questionable and the use of supercritical carbon dioxide as the solvent was also considered. Its inherent properties include non-flammability, mild critical conditions, tuneable solubility near to the critical point and very low environmental impact. The reaction was operated using a continuous high pressure fixed bed. Results concerning yield and selectivity are presented
MM. Friedel et Crafts ont obtenu l'acide mellique par l'oxydation de l'hexaméthylbenzine
No full textFriedel Charles. MM. Friedel et Crafts ont obtenu l'acide mellique par l'oxydation de l'hexaméthylbenzine. In: Bulletin de la Société minéralogique de France, volume 3, 7, 1880. pp. 189-190
Christel und Gretchen : Eine ländliche Posse in drey Aufzügen / Von Friedel
Full text linkCHRISTEL UND GRETCHEN : EINE LÄNDLICHE POSSE IN DREY AUFZÜGEN / VON FRIEDEL
Christel und Gretchen : Eine ländliche Posse in drey Aufzügen / Von Friedel (1)
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Friedel-crafts alkylation of nitrogen heterocycles using [Bmim] [OTf] as a catalyst and reaction medium
No full textFriedel-Crafts alkylation of nitrogen heterocycles, such as indoles and pyrroles, can be carried out in ionic liquids under mild conditions to afford the corresponding alkylated product in moderate to good yield
Viris Generelissimis Praeno-|bilissimis atque Doctissimis| Fautoribus et Amicis| Suis omnibus| Album hoc| Sanctum esse| voluit| Leopoldus Fridericus Friedel| Anhalt Cöth.. L.L.C. : Stammbuch Leopold Friedrich Friedel
No full textEnthält 83 Stammbucheinträge u.a. von Siegmund Jacob Baumgarten; Justus Henning Böhmer; Johann Samuel Friedrich Böhmer; Heinrich David Emanuel Friedel (1712/14-1776, Jurist, Bruder des Stammbuchbesitzers); Johanne Elonore Henriette Friedel (1712-1776, Frau des H.D. E. Friedel); Carl Gottlieb Knorre; Johann Henrich Kratzenstein; Daniel Nettelbladt; Christian Erhard Salmuth; Daniel Straehler; Theodor Christoph Ursinus; Christian WolffHandschrift DE-3, GND 2024680-8, Signatur: Yg St. 8° 66/21Einband: Ganzlederband; Glanzleder über Pappe; Streicheisenlinien, Rollen- und Plattenstempel (Goldpressung); Rückenprägung mit Plattenstempel (Adelskrone) und Filete (Golldpressung); Vorderdeckel mit geprägtem Monogramm: L.H.B und Jahreszahl: 1748; zweifarbige Kapitale; leicht gepunzter Goldschnitt, Spiegel Bronzefirnispapier.Zustand: Papier leicht gebräunt und fleckig; Einband mit leichten Gebrauchsspuren; Ecken und Kanten berieben und bestoßen.Exlibris der Vorbesitzers (Stula) im VorderspiegelEintragungsorte: Berlin, Dessau, Halle (32), Köthen, Magdeburg, ZerbstNoten S. 286; Bleistiftzeichnung und montiertes Wappen S. 455
Margarete, Ottilie, Salomon, Rudi, Friedel, Papa u. Mama [?] an Herman Grimm (1 Brief)
No full textMARGARETE, OTTILIE, SALOMON, RUDI, FRIEDEL, PAPA U. MAMA [?] AN HERMAN GRIMM (1 BRIEF)
Margarete, Ottilie, Salomon, Rudi, Friedel, Papa u. Mama [?] an Herman Grimm (1 Brief) (Br5787)
Brief 5787 (Br5787
Oral history interview with Jean Friedel, November 28, 1995
No full textOral history interview with Jean Friedel, conducted by Mary Hurlbut Cordier on November 28, 1995. Friedel discusses how she came to teach women’s athletics at WMU, the changes to women’s physical education in response to Title IX, budgeting constraints, and the condition of various buildings used for physical education. She shares what it was like to be a women in higher education in the 1960s and 1970s, the environment of WMU throughout her career, collaborations with other faculty, and her enjoyment working with students. Jean Friedel coached seven women’s sports, including basketball, field hockey, volleyball, gymnastics and track and field, at WMU during her 29-year tenure from 1960-1989.No transcript available
Homogeneous Friedel–Crafts Alkylation
No full textSince its discovery in 1877, Friedel–Crafts alkylation has been one of the most significant reactions in organic chemistry. The breadth of this reaction has increased over 130 years, and it is now moving toward a more environmental friendly and economically viable homogenous approach. This reaction could potentially be carried out in a continuous or supercritical manner. For the alkylation of anisole and indole, a variety of catalysts were used, including solid acid catalysts, ionic liquids, and supported ionic liquids. Aside from the process efficiency, the rising tendency of Friedel–Crafts alkylation ensures its environmental friendliness and energy economy. Various catalysts for Friedel–Crafts alkylation in the homogeneous medium were discussed in this chapter along with their industrial viability. The viability of their business and future obstacles are also discussed.No Full Tex
Friedel
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