PolytheneSam (Master Searcher)
04-20-02 20:48
No 299552
      Electrochemical reductive amination  Bookmark   

This reference is from Soviet Electrochemistry Vol. 28, No. 4, (1992), page 476-484 mentioned here Post 289268 (PolytheneSam: "electroamination", Stimulants) .  There's nothing in it on amination of P2P or MDP2P, but it seems like it should work with them.
J. Org. Chem. USSR Vol 28, No. 3, (1992) is on electrochemical reductive amination of aldehydes and might be applicable to amination of indole-3-acetaldehyde with dimethylamine.

I put this in html form since the xerox copy wasn't too good.

http://www.geocities.com/apis_mellifica2002/SovEle28.html
http://www.geocities.com/apis_mellifica2002/SovEle28b.html
http://www.geocities.com/apis_mellifica2002/SovEle28c.html
http://www.geocities.com/apis_mellifica2002/SovEle28d.html
http://www.geocities.com/apis_mellifica2002/SovEle28e.html
http://www.geocities.com/apis_mellifica2002/SovEle28f.html
http://www.geocities.com/apis_mellifica2002/SovEle28g.html
http://www.geocities.com/apis_mellifica2002/SovEle28h.html
http://www.geocities.com/apis_mellifica2002/SovEle28i.html


http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    Rhodium
(Chief Bee)
04-20-02 22:50
No 299579
      Nice!  Bookmark   

Great! I'm sure you have nothing against me merging the files to one document and post it on my page with credits to you?
 
 
 
 
    PolytheneSam
(Master Searcher)
04-20-02 23:10
No 299587
      electrochemistry  Bookmark   

I still need to add the references listed on page 484.  I could just upload a tiff file version.  The other pictures could be better quality, too.

http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    PolytheneSam
(Master Searcher)
04-20-02 23:51
No 299598
      references  Bookmark   

Here's the references.
http://www.geocities.com/apis_mellifica2002/SovEle28ref.tif

http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    Scooby_Doo
(Hive Bee)
04-23-02 06:38
No 300351
      Nice x2  Bookmark   

Yeah nice work Sam, that is a kickass ref. The yields may not be as high as other methods but those conditions have got scale up written all over them.laugh
 
 
 
 
    PolytheneSam
(Master Searcher)
04-28-02 23:33
No 302695
      related article  Bookmark   

Here's something related to this. 
../rhodium/chemistry /electroreductive.amination.txt

http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    Scooby_Doo
(Hive Bee)
04-29-02 06:47
No 302864
      scale up  Bookmark   

Yes its all good, but yours gives some boundaries to work in and maybe a little hint on what to expect on scale up.

Talking of scale up, one of the major hurdles will be power, I figure to get results such as Labtop's Bees are going to need lots of Amps probably around the 100-200 amps range for a decent batch.  Scooby has done some asking around, options include batteries, DC generators or bridged rectifiers.

Batteries sound good for smaller cheap research runs maybe 3 or 4 truck batteries might give you 20 or so amps for a few hours.

DC Generators might be good for the outdoor Bees who have limited power supply anyway. Not so good in the apartment, plus getting those  5000 lt tanks up the stairs or elevator might be a little hard!?!laugh

3 phase bridged rectifiers for the industrial Bee up to several thousand amps expensive but if you need this sort of ampage I guess price wouldn't really be a concern.wink Although ripple might cause some problems.

"Scooby you crazy nutbar what kinda cell are you going to run that current through!" crazy

Plate and frame type would be the most successful. Imagine a stack of sandwiches with rods running vertically through them to squeeze them together. With your electrode plates placed: anode gap membrane gap cathode gap membrane gap anode etc then pipes connecting the anode gaps run the anolyte and the pipes connecting the cathode gaps running the catholyte. Both the electrolytes will need to run though heat exchanges to cool them working at those types of currents. The good thing is that the whole shebang can be made out of plastic as long as the heat build-up is minimized i.e. the use of large busbars, low electrolyte resistance and good cooling.
 
 
 
 
    PolytheneSam
(Master Searcher)
05-10-02 01:59
No 306860
      patents  Bookmark   

Some interesting patents worth looking at are

Patent US3361653 details, electrode, separator materials, etc., production of benzene from chlorobenzene (will it work for paradichlorobenzene?)

Patent US3445354 detailed, explains overpotential

Patent US5266731 amines from nitriles, cobalt oxide cathode

Patent US5919349 electrochemical reduction of organic compounds


http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    PolytheneSam
(Master Searcher)
06-03-02 01:45
No 316952
      Here's a lot of electrochemical stuff from ...  Bookmark   

Here's a lot of electrochemical stuff from Chem_Guy/jim.
Post 222019 (jim: "Birch references from jim", Stimulants)

http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    PolytheneSam
(Master Searcher)
06-03-02 04:24
No 317018
      Condition/preparation of the lead cathode seems ...  Bookmark   

Condition/preparation of the lead cathode seems to be important so I wrote this.

Here's some tips on using lead (and some other materials) as cathodes.  I saw a post before on making a circular cathode (lead?) which surrounds the anode and separator so that you have equal distances between the anode and cathode so that you have more or less constant current density on the cathode.  The only one I found was Post 38186 (Malcolm: "Electrocatalytic reduction, too good to be true?", Stimulants) .  I'll just copy relevant parts from xerox copies I have:


The nature of the cathode material is an important factor in electrolytic reduction.  By using a material with a high hydrogen overvoltage, a higher cathode potential and, therefore, greater reducing energy may be obtained, without the liberation of gaseous hydrogen.1  Tafel2 showed that the reduction of substances like pyridine and compounds containing the keto group, reducible only with great difficulty, can be accomplished readily at cathodes of lead and mercury -- metals with high hydrogen overvoltages -- whereas little or no reduction takes place at a platinum cathode.  Frequently, reduction proceeds further and with a higher current efficiency at a mercury than at a lead cathode.  From the results of his experiments, Tafel concluded that "substances which are difficult to reduce can only be reduced in sulphuric acid solution, when such cathodes are employed as give a particularly high overvoltage."  In order to secure this high hydrogen overvoltage, it is essential that the metal of the cathode be free from impurities, as often even traces of foreign metals lower the overvoltage considerably. When lead cathodes are used in these reductions, they first must be treated electrolytically.3
     It has been suggested that the cathode potential in electrochemical reduction processes can be controlled by means of a specially designed circuit.4
     (b) Physical Condition of the Cathode. The physical condition of the cathode may exert an influence on electrochemical reduction.5  In the electrochemical reduction of benzoic acid at cathodes of 99.99+ per cent lead, Swann and Lucher obtained better yields of benzyl alcohol when the metal was extruded than when it was cast; and they found that after prolonged use the activity of the cathode decreased, owing to diminution in the crystal size of the lead surface as well as to the formation lead sulphate.  These same investigators found the yield of benzyl alcohol at a cadmium cathode to be associated with the ability of the metal to undergo a macro etch of its surface, the yield being approximately proportional to the extent of etching which the surface underwent.





Since a high current density not only raises the cathode potential but also decreases the concentration of the depolarizer in the vicinity of the cathode, electrolytic reduction is, in general, more rapid and complete the lower the current density.  That is, a large cathode surface should be employed.  Obviously, an increase in the concentration of the depolarizer will also contribute to more efficient reduction.  Effective stirring is likewise advantageous.





(f) Applications of Electrochemical Reduction.  In the practical application of electrochemical reduction, it must be remembered that the products formed at the cathode are likely to be oxidized at the anode.  In order to prevent this from happening, the anode is frequently separated from the cathode by a diaphragm.5  The portions of electrolyte contained in the sections thus formed are termed the anolyte and catholyte, respectively.  The same end can sometimes be attained by employing a high anodic current density (ie., a small anode surface) or, in alkaline solutions, iron or nickel anodes -- metals with the smallest oxygen overvoltages.




from Principles and Applications of Electrochemistry 4th Edition H. J. Creighton Vol. 1 1943


Also,


In addition to the conductors themselves small quantities of salts and other compounds are sometimes added to promote reduction or oxidation (see section on factors influencing reduction and oxidation, pages 415-16 and 440).  Promoters of the reduction are:  salts of copper, titanium, tin, lead, vanadium, and molybdenum, arsenic and antimony oxides, and ketones.  Promotors of oxidation are oxidizing agents such as potassium ferricyanide, and ceric and manganic salts.





Another factor which may influence the efficiency of a cathode is the orientation of the crystals in the cathode.  The yields of benzyl alcohol at extruded lead rod cathodes as received were decidedly higher that those at the same lead after it had been recast.56  It is possible that some preferred orientation of the crystals had occurred when the lead recrystallized after extrusion.  The yields of benzyl alcohol compared favorably with those obtained at lead electroplated from a perchlorate bath....

....Surface Treatment.  Caffeine is easily reducible at the spongy surface of "prepared" (see page 418) and also at a roughened lead cathode when not reducible at a smooth surface.63





(page 418)
A lead cathode is "prepared" by a modification of the Tafel80 method whether it is to be used in acid or in alkaline solution.  The cathode to be use is placed as before in a 20% solution of sulfuric acid surrounded by a sheet of lead.  The cathode is used as anode under the conditions described above except that the current is allowed to flow for 5 minutes.  A layer of chocolate brown lead oxide forms on the surface of the lead used as anode.  The polarity is reversed and the current again allowed to flow for 5 minutes.  The lead oxide is reduced to spongy metallic lead.  The cycle is repeated.  At the end of the second cycle a third is begun, but the cathode is left in the oxidized condition.  It is washed thoroughly with distilled water before being used in the reduction.




from Technique of Organic Chemistry Vol. II, Catalytic, Photochemical, Electrolytic Reactions, 2nd edition, Interscience Publishers, Inc. New York, 1956



http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    PolytheneSam
(Master Searcher)
06-08-02 20:43
No 318910
      references  Bookmark   

Here's the references which doesn't seem to work anymore in Post 299598 (PolytheneSam: "references", Novel Discourse) .  jpeg images seem to get really distorted by geocities.
http://www.geocities.com/apis_mellifica2002/SovEle28ref2.html




http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious
 
 
 
 
    PolytheneSam
(Master Searcher)
06-09-02 04:09
No 319017
      indigo  Bookmark   

Here's a good article on the electrochemical reduction of indigo.
http://www.tech.chem.ethz.ch/roessler/chimia.pdf

A good thing to study is:
http://www.compusmart.ab.ca/plambeck/che/p102/p02071.htm
http://www.compusmart.ab.ca/plambeck/che/p102/p02072.htm
http://www.compusmart.ab.ca/plambeck/che/p102/p02073.htm
etc.

A salt bridge is explained here.
http://www.compusmart.ab.ca/plambeck/che/p102/p02073.htm
http://www.compusmart.ab.ca/plambeck/che/p102/p02092.htm

(link to next page is at the bottom of each page)


http://www.geocities.com/dritte123/PSPF.html
The hardest thing to explain is the obvious