Detail preparation

One may also wonder why a volume with syntheses in the title is devoid of detailed preparations. These have been consciously omitted because inclusion of more than just a few would have made the book quite lengthy and the arbitrary choice of procedures would have added to the problem noted above. We have included mention of key experimental details in numerous cases but feel that the reader would be far wiser to refer to the original literature in performing a preparation than following a recipe from a book. The orginial literature would be necessary in any event since it would have been impossible to include spectral data in the preparations. 

Inorganic Syntheses, 27, Chap. 3 pp. 71-135 (1990), give.s several detailed preparations. 

Use of ethyl trimethylsilylacetate (detailed preparation given) and TBAF (drying details Fluka trihydrate dried over P2Os/48 h/0.1 mmHg, and then powdered in a dry atmosphere) for the preparation of (Z)-3-trimethylsilyl-ioxypent-2-ene from pentan-3-one. 

Detailed preparation from LiCN (from LiH and acetone cyanohydrin) and TMSC1, followed by its reaction with p-bcnzoquinone in the presence of 18-Crown-6 and KCN. 

Oxidation with mepba — -hydroxyketones, using the reaction of isophorone dienol ether (detailed preparation given), and Et3N.HF cleavage of the intermediate silyl ether. 

At this stage in planning, the essential study design information listed below should be determined and a written study plan (i.e., protocol) including these key study details prepared. A formal, pre-approved study plan is required for field soil dissipation studies conducted under Good Laboratory Practice (GLP). A written study plan for non-GLP studies is highly recommended since the document serves as valuable guidance for study personnel. 

Waggoner, K. M. Hope, H. Power, P. P. Angew. Chem. Int. Ed. Engl. 1988, 27, 1699. Six-membered heterocycles [RMER ]3 have been subject to detailed preparative and theoretical studies since they are isoelectronic to borazine B3N3Hs. However, it was demonstrated that only B3P3-heterocycles exhibit a considerable delocalization of the 6 k-electrons, whereas the delocalization in other six-membered heterocycles of the desired type contributes very little to their stabilization. Power P. P. J. Organomet. Chem. 1990, 400, 49. 

Running buffer composition, including a detailed preparation procedure with the order of addition of the components... 

Vanadium phosphate catalysts were prepared by heating V2O4, phosphorus acid, either H3PO4 or H4P2O7, and water together in an autoclave at 145°C for 72 hours. Afterwards, the solid produced was recovered, washed with distilled water and dried in air at 120°C for 16 hours. Detailed preparation procedure is described in [79]. Such prepared precursors were activated in n-butane/air at 400°C to form the final catalysts. TEM and EELS are used to study the catalysts in Philips CM200 PEG microscope. 

Several substitution reactions are catalyzed by iron ions (Galli and Bunnett 1984). A detailed preparative study was reported on the ferrous ion-initiated Sr I reactions of haloarenes with the... 

Excerpt 3D Illustrates two additional points regarding naming chemicals in move 1 First, if all chemicals used were of the same grade and from the same company, state only the grade and company, not the names. The names will be mentioned In move 2, when the procedures In which the chemicals were used are described. Second, only those chemicals that were used as received, required minimal preparation (e.g., distilling or degassing), or were prepared according to literature methods (which should be cited in the text) are mentioned. Chemicals that require more detailed preparation steps are described in move 2. 

Learn the best strategies for solving tough problems in step-by-step detail Prepare effectively for exams and save time in doing homework problems Use the indexes to quickly locate the types of problems you need the most help solving Save these books for reference in other courses and even for your professional library... 

Almotriptan has also been synthesized via decarboxylation of the carboxylic acid intermediate 65, but a detailed preparation of 65 was not provided in the patent literature (Scheme 22)." The patent indicates that the carboxy indole 65 was prepared according to the method of Gonzalez.°° Thus, (2-oxo-tetrahydro-3-furanyl)-glyoxylic acid ethyl ester (62) was heated in aqueous H2SO4 to give 2-oxo-5-hydroxypentanoic acid in situ, which was treated with hydrazine 59 to produce hydrazone 63. Fischer cyclization of 63 using HCl gas in DMF gave the lactone 64, which was converted to carboxylic acid 65. Decarboxylation of 65 was catalyzed by cuprous oxide in quinoline at 190 °C to afford almotriptan (5)." ... 

A wide variety of chromones has been prepared by this method since its introduction (01CB2475), and the literature abounds with examples. A fully detailed preparation of 3-ethylchromone is available (5SOSC(3)387). The presence of substituents in the aromatic ring of the acetophenone has minimal effect on the course of the reaction both electronreleasing and electron-withdrawing substituents are compatible with the synthesis. 

It is usual to produce 2,4,6-trisubstituted pyrylium salts by this method, otherwise isolation of the products is difficult. Although yields are only fair, considerable variation in the substituents is possible and some satisfactory examples are known. The detailed preparation of 2,4,6-trimethylpyrylium perchlorate also includes a brief survey of methods and merits of the procedure (73OSC(5)ll06). 

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