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All 8 posts | Subject: Electro solvent | Please login to post | Down | |||||
masterofpuppets (Hive Bee) 12-31-01 01:23 No 251467 |
Electro solvent | |||||||
If one was having difficulty finding a solvent to disolve a substance, could a certain bee just use a solvent with a similar specific gravity to the substance to hold it, and then carry out an electrolysis reaction. I guess that simply, what I am asking is whether or not a substance has to be disolved in a solvent for it to be electrically reduced. You are unique....just like everyone else....... |
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terbium (Old P2P Cook) 12-31-01 06:09 No 251530 |
Re: Electro solvent | |||||||
If one was having difficulty finding a solvent to disolve a substance, could a certain bee just use a solvent with a similar specific gravity to the substance to hold it, and then carry out an electrolysis reaction. No. I guess that simply, what I am asking is whether or not a substance has to be disolved in a solvent for it to be electrically reduced. Yes. Still trying to electroreduce phenylalanine? |
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masterofpuppets (Hive Bee) 01-01-02 07:42 No 251710 |
Re: Electro solvent | |||||||
Hey, why would I ever want to electro reduce phenylalanine??? I mean, what would be the point of that??? Although, if one did want to do that, how would u suggest that one solves the problem of a solvent? Oh, found an electro chem book that mentioned that in concentrated sulfuric acid (60+%) that carboxylic acids could be reduced at a lead electrode. Anyone heard/tried this?? You are unique....just like everyone else....... |
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Prdy2GO (Hive Bee) 01-02-02 06:08 No 251891 |
Re: Electro solvent | |||||||
Oh, found an electro chem book that mentioned that in concentrated sulfuric acid (60+%) that carboxylic acids could be reduced at a lead electrode. Anyone heard/tried this?? Yes what about it? Don't look at me I didn't do it! |
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joyman (Hive Bee) 01-02-02 07:43 No 251910 |
Re: Electro solvent | |||||||
master, whats wrong with propelyene carbonate?. from what i read although phenylalanine is only slightly soluble, wouldnt it make sense to just use small ammounts gaa to keep the ratio in molar order (ie a 1/3 phenylalanine to acetic - need an excess to avoid phenylalanine forming a dimer with itself). you would then have very weak solution of phenylalanine and gaa. you could continuously add the acetic acid as it gets used up and as more phenylalanine disolves. i dont see that the fact phenylalanine is only slightly soluble is a real problem (make it a process of continuously adding phenylalanine and gaa). - but then im no chemist. whats this reduction your talking about? - sounds interesting - is it to an alcohol or all the way to Me. |
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foxy2 (Distinctive Doe) 01-02-02 07:59 No 251917 |
Re: Electro solvent | |||||||
Ummm, Are these guys trying to do what master wants? This article looks like the shit Strategy for controlling the Kolbe electrosynthesis in the presence of aromatic fragments and amino groups in the molecule. Smirnova, N. V.; Neganova, E. G.; Astaf'ev, E. A.; Petrii, O. A.; Tsirlina, G. A.; Beletskaya, I. P. Southern Russian State Technical University, Russia. Russ. J. Electrochem. (2001), 37(9), 893-898. Journal written in English. Abstract A general characteristic of processes that occur during anodic oxidn. of phenylacetic and phenylpropionic acids and derivs. of a- and b-amino acids on platinum electrodes in methanol and mixed pyridine-methanol solns. is given. From preparative electrolyzes in stagnant and flow-through reactors, conditions are detd. under which the dimerization (Kolbe electrosynthesis) is least complicated by the formation of polymer products. Properties of removed electrodes, on which stable polymer films formed during the electrosynthesis, are examd. For films formed in certain conditions on the cathode, the presence of a quasi-reversible redox transition is demonstrated. Such films contain disperse platinum codeposited with polymer as a result of the anode dissoln. in the cells with common compartments. In principle, the film-modified electrodes can be used for controlling anodic decarboxylation. Citations 1) Schafer, H; Comprehensive Organic Synthesis: Selectivity, Strategy, and Efficiency in Modern Organic Chemistry 1991, 3, 633 2) Eberson, L; Organic Electrochemistry: An Introduction and a Guide 1973 3) Weiper-Idelmann, A; Acta Chem Scand 1998, 52, 672 4) Sugiya, M; Bull Chem Soc 2000, 73, 705 5) Sugiya, M; Chem Lett 1998, 479 5) Volckaerts, E; Bull Soc Chim Belg 1992, 101, 497 6) Linstead, R; J Chem Soc 1951, 2854 7) Linstead, R; J Chem Soc 1952, 3624 8) Coleman, J; J Chem Soc, Perkin Trans 2 1974, 1064 9) Ross, S; J Org Chem 1969, 34, 2923 10) Vijh, A; Chem Rev 1967, 67, 623 11) Fioshin, M; Itogi Nauki Tekh Ser: Elektrokhimiya 1972, 8, 273 12) Mirkind, L; Elektrosintez i mekhanizm organicheskikh reaktsii (Electrosynthesis and Mechanism of Organic Reactions) 1973, 181 13) Andrieux, C; J Am Chem Soc 1997, 119, 4292 14) Yan, J; J Appl Electrochem 1996, 26, 175 15) Gordon, A; A Handbook of Practical Data, Techniques, and References 1972 16) Anon; Beilstein Handbook of Organic Chemistry 1988, 14, 302 17) Anon; Beilstein Handbook of Organic Chemistry 1988, 14, 493 18) Lokensgard, J; J Org Chem 1985, 50, 26 18) Lokensgard, J; J Org Chem, 5609 19) Anon; Beilstein Handbook of Organic Chemistry 1982, 5, 598 20) Anon; Beilstein Handbook of Organic Chemistry 1982, 5, 616 21) Anon; Electroactive Polymer Electrochemistry 1994 21) Anon; Electroactive Polymer Electrochemistry 1996 22) Fedorova, A; Elektrokhimiya 1967, 3, 742 Emulsion electrosynthesis in the presence of power ultrasound. Biphasic Kolbe coupling processes at platinum and boron-doped diamond electrodes. Wadhawan, J. D.; Del Campo, F. J.; Compton, R. G.; Foord, J. S.; Marken, F.; Bull, S. D.; Davies, S. G.; Walton, D. J.; Ryley, S. Physical and Theoretical Chemistry Laboratory, Oxford University, Oxford, UK. J. Electroanal. Chem. (2001), 507(1-2), 135-143. Abstract The electrochem. oxidn. of aliph. carboxylic acids, hexanoic, heptanoic, and lauric acid, under biphasic conditions was studied as a model system for ultrasound enhanced Kolbe electrosynthesis processes. Power ultrasound was used to generate an in situ emulsified medium and to remove reaction products continuously from the electrode surface. A clean and highly efficient process at platinum electrodes with formation of 'one electron' products only occurs in marked contrast to processes in monophasic media. For hexanoic acid the Kolbe dimer product R-R is formed in up to 75% yield with 45% current efficiency at 0.18 A cm-2 c.d. and in the presence of 190 W cm-2 ultrasound. The mechanism is explained in terms of a dynamically modified electrode surface, at which hydrophobic products are immediately 'trapped' via partitioning into a nonpolar org. phase and transported away into the emulsion system. Kolbe electrosynthesis is undertaken both at platinum electrodes and at free-standing polycryst. boron-doped diamond electrodes, to minimize the surface erosion effect induced by power ultrasound. The type and yield of products obtained from the biphasic Kolbe electrolysis process at diamond electrodes are essentially identical to those obsd. at platinum and based on this observation, the presence of a biphasic reaction layer at the electrode surface is postulated to govern the process. Citations 1) Fees, H; Techniques of Electroorganic Synthesis Part 3 1981, 81 2) Rusling, J; J Electroanal Chem 1997, 439, 89 3) Carrero, H; Electrochim Acta 1999, 45, 503 4) Schweizer, S; Chemosphere 1994, 28, 961 5) Marken, F; Chem Commun 1997, 955 6) Marken, F; Electrochim Acta 1998, 43, 2157 7) Ackermans, R; Chem Commun 1999, 1115 8) Atobe, M; Denki Kagaku 1998, 66, 556 9) Behrend, O; Ultrason Sonochem 2000, 7, 77 10) Ludwig, H; Wiss Z Techn Univ Dresden 1990, 39, 163 11) Walton, D; Adv Sonochem 1996, 4, 205 12) Compton, R; Electroanalysis 1997, 9, 509 13) Marken, F; J Electroanal Chem 1996, 415, 55 14) Kado, Y; Electrochemistry 2000, 68, 262 15) Mason, T; Sonochemistry: Theory, Applications and Uses of Ultrasound in Chemistry 1988 16) Atobe, M; Electrochemistry 1999, 67, 1114 17) Fujiwara, H; J Chin Chem Soc 1998, 45, 175 18) Chyla, A; Chem Commun 1989, 603 19) Walton, D; Ultrason Sonochem 1994, 1, S23 20) Pleskov, Y; Russ Chem Rev 1999, 68, 381 21) Swain, G; MRS Bull 1998, 23, 56 22) Fujishima, A; J Electroanal Chem 1999, 473, 179 23) Goeting, C; J Electroanal Chem 1998, 442, 207 24) Angus, J; Front Carbon Technol 1999, 9, 175 25) Okino, F; Electrochem Solid State Lett 1999, 2, 382 26) Goeting, C; New Diam Front Carbon Technol 1999, 9, 207 27) Gandini, D; New Diam Front Carbon Technol 1999, 9, 303 28) Marken, F; Ultrason Sonochem 1996, 3, S131 29) Compton, R; Chem Commun 1998, 1961 30) Saterlay, A; Electroanalysis 1999, 11, 1083 31) Jacob, S; Thesis Oxford University 1997 32) Fichter, F; Helv Chim Acta 1927, 10, 869 33) Fichter, F; Helv Chim Acta 1935, 18, 445 34) Brockman, C; Electroorganic Chemistry 1926 35) Wilke, C; AIChE J 1955, 1, 264 36) Torii, S; Organic Electrochemistry 1991 37) Compton, R; J Phys Chem 1994, 98, 12410 38) Goeting, C; Diam Rel Mater 1999, 8, 824 39) Saterlay, A; Analyst 1999, 124, 1791 40) Michaud, P; Electrochem Solid State Lett 2000, 3, 77 41) Utley, J; Techniques of Electroorganic Synthesis Part 1 1981 42) Buback, M; Z Phys Chem 1997, 199, 229 43) Fujimori, K; Organic Peroxides 1992, 319 44) Hinton, C; Chem New Zealand 1998, 62, 12 45) Janzen, E; J Am Chem Soc 1968, 90, 5909 46) Janzen, E; J Am Chem Soc 1969, 91, 4481 Novel synthesis of some specialty chemicals by electroorganic reaction. Nishiguchi, Ikuzo; Hirahsima, Tsuneaki; Shundo, Ryushi; Matsubara, Yoshiharu. Osaka Munic. Tech. Res. Inst., Osaka, Japan. Editor(s): Little, R. Daniel; Weinberg, Norman L. Electroorg. Synth., [Manuel M. Baizer Meml. Symp.] (1991), Meeting Date 1990, 331-9. Publisher: Dekker, New York, N. Y General Review written in English. Abstract New electrosynthetic methods are reviewed for some specialty chems., such as synthesis of Nojigiku alc. from tricyclene, stereoselective cleavage of polycyclic methylcyclopropanes by anodic oxidn. synthesis of bis(4-nitrophenyl)sulfone and bis(4-nitrophenyl)sulfoxide by anodic oxidn. and synthesis of penicillanic acid derivs. by electrooxidn. Novel synthesis of 1-triacontanol by mixed Kolbe's coupling and electroreductive C-acylation of arom. carboxylic acids and epinephrine derivs. are described. Foxy STILL needs to get laid!!! |
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masterofpuppets (Hive Bee) 01-03-02 08:05 No 252182 |
Re: Electro solvent | |||||||
Prdy2GO: I was curious if it would "go all the way" to reducing the cooh to ch3. Everyone else although both DMF and propylene carbonate work as solvents, I am attempting to find ways to make this synth work which is totally OTC/just using very common chems - therefore preventing restriction by the nasty authorities. You are unique....just like everyone else....... |
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PolytheneSam (Master Searcher) 06-03-02 00:03 No 316963 |
>Oh, found an electro chem book that mentioned ... | |||||||
>Oh, found an electro chem book that mentioned that in concentrated sulfuric acid (60+%) that carboxylic acids could be reduced at a lead electrode. Anyone heard/tried this?? I have a reference on an experiment where benzoic acid (in dilute sulfuric acid) is reduced electrochemically to benzyl alcohol using a prepared lead cathode. http://www.geocities.com/dritte123/PSPF.html The hardest thing to explain is the obvious |
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