synthetikal.com Forum Index


Built by the Community for the Community
 Forum IndexForums 
 
   Rhodium Chemistry ArchiveRhodium   The ArcHiveThe Hive   Shop   ProfileProfile   Log inLog in   RegisterRegister 
---- via BzMgCl/acetaldehyde methyleneimine grignard?
Page 1 of 1
Post new topic   Reply to topic    synthetikal.com Forum Index -> Misc. Stimulants
Author Message
IndoleAmine
Dreamreader Deluxe
Joined: 09 Feb 2005
Posts: 681
Location: Bahamas
18717.10 Points
View Single Post97
---- via BzMgCl/acetaldehyde methyleneimine grignard?

 Wed Feb 09, 2005 9:28 am		 Reply with quote
Does any bee know about the reliability of the following reaction?

C6H5Ch2Cl + Mg --(Et2O)--> C6H5Ch2MgCl grignard reagent

CH3CHO + CH3NH2 --( - H2O)--> CH3CHNHCH3 (acetaldehyde methylamine schiff base)

C6H5CH2MgCl + CH3CHNHCH3 --(grignard rxn)--> {Mg complex}

{Mg complex} --( aequ. HCl hydrolysis )--> C6H5CH2CH(NHCH3)CH3

There are two independent descripitions of the above rxn, one in an italian chem journal ("Gazz.Chim." I think), and the other one by someone called "Lenno Lantruculus" - both refs can be found at any of the many rhodium mirrors.

The question is: Is this a reliable procedure or bullshit?

Anyone with experience and/or knowledge in the field?
Back to top
java
Consumer
Joined: 07 Feb 2005
Posts: 736
Location: The Mexican Republic
21796.14 Points
View Single Post138
Gringnard Reactions

 Thu Feb 10, 2005 4:39 am		 Reply with quote
There is a nice review of gringnard reactions for the reader of this thread to guide you through the reaction.............java
Back to top
Hex

Joined: 07 Apr 2005
Posts: 29
1384.74 Points
View Single Post3579

 Sat Apr 16, 2005 3:10 pm		 Reply with quote
To IndoleAmine:
The technique, specified by you, was checked in Russian Hyperlab. Anybody could not receive results specified by the offered circuit. A problem that formed imine is astable and easily polimerized. I believe, that the following circuit of transformations is possible:


C6H5CH2CHO + CH3NH2 (or C2H5NH2) ---> C6H5CH2CHNHR(phenylacetaldehyde methylamine (or ethyl amine) schiff base)

CH3X + Mg ---> CH3MgBr (grignard reagent), where X=Cl or Br

CH3MgX + C6H5CH2CHNHCH3 --(grignard rxn)--> [Mg complex]

[Mg complex] --- [aq. HCl hydrolysis ] ---> C6H5CH2CH(NHCH3)CH3 (or N-ethylamphetamine Smile


C6H5CH2CHNHCH3 (C6H5CH2CHNHCH2CH3) - These imines are more stable. They can simply be synthesized by aceotropic rxn of amine and phenylacetaldehyde in benzene.
Back to top
CherrieBaby
chouchou
Joined: 01 Mar 2005
Posts: 67
3070.02 Points
View Single Post3625

 Sun Apr 17, 2005 4:30 pm		 Reply with quote
a) I haven't tried it, but this rxn has an undistinguished history in my memory. The first mention I ever heard was in a Forensic Science article [R. S. Frank, J. For. Sci., Vol 28, No 1, p18-31 (1983)]. He said that "In the next most popular method (less than 10%), the product of an acetaldehyde/methylamine reaction was refluxed with benzylmagnesium chloride. It should be noted that at none of the 16 laboratories using this reflux method was methedrine actually synthesized. The reason is that the order in which the precursors are added described in an underground publication entitled Whole Drug Manufacturer's Catalog Transmittal by Chewbacca Darth differs from the normal synthesis procedure."

https://www.synthetikal.com/Rhodiums_pdfs/chemistry/clandestine.html

b) Jerry March mentions it: 4e, Section 6-35, p934. 5e, Section 16-35, p1216.

It seems, from reading March, that there could be a problem making simple amphetamine but it should be OK to make methamph. this way. He says that "for the addition of an organometallic compoundto an imine to give a primary amine, R' in RCH=NR' would have to be H, and such compounds are seldom stable."

In, 5e, March references:

(1) K. Harada in Patai's The Chemistry of the Carbon-Nitrogen Doouble Bond, Wiley, 1970, pp266-272.
(2) Kharasch; Reinmuth, "Grignard Reactions of Nonmetallic Substances", Prentice-Hall, 1954, pp1204-1227.
(3) Wang, Dai, Hou, Zhang. Tetrahedron Lett. 1996, 37, 4187
(4) Bambridge, Begley, Simpkins. Tetrahedron Lett. 1994, 35, 3391
(5) Enders, Reinhold. Tetrahedron Asymmetry, 1997, 8, 1895
(6) Andersson Johansson, Tanner. Tetrahedron 1998, 54, 11549
(7) Tomioka, Inoue, Shindo, Koga. Tetrahedron Lett. 1991, 32, 3095.

c) Below is the relevant entry for Kharasch; Reinmuth. They reference Campbell, Helbing, Florkowski & Campbell, JACS 70, 3868, (1948), which has been posted by me already:

https://www.synthetikal.com/synthforum/viewtopic.php?t=638

Morris Kharasch; Reinmuth, Grignard Reactions of Nonmetallic Substances, p 1204-1227; Prentice-Hall, 1954 from page 1204:
Quote:
Ch. XIX, Nitrogen Compounds

Compounds Containing The Grouping -N=C<

Aldimines. Busch[9] reported that Grignard reagents react additively with benzylidene-aniline, and studied the reaction further with Rinck,[10] extending it to other methylene-imines with Leefhelm.[11]

In general, addition to methylene-imines of the type R'N=CHR" takes place under relatively mild conditions (i.e., at or below the boiling point of ethyl ether) to give fairly good yields of products which, upon hydrolysis, liberate secondary amines.

RMgX + R'N=CHR" ==> R'N(MgX)CHRR"

R'N(MgX)CHRR" + H2O ==> R'NHCHRR" + MgXOH

A representative preparation is described by Campbell et al.[12] "To one mole of n-propyl-magnesium bromide in 250 mL. of dry ether was added a solution of 66.5 g. (0.5 mole) of benzylidene-ethylamine in 50 mL. of dry ether, over a period of one and one-half to two hours; the reaction mixture was refluxed for several hours and allowed to stand overnight. It was hydrolyzed by pouring onto ice and hydrochloric acid."

The authors observe, as a matter of practical interest, that consistently good (60 to 30 percent) yields are obtained when Grignard reagent and base are used in one-to-one molecular ratio only in cases of the more reactive Grignard reagents (e.g., methyl-magnesium bromide) and the simplest aldimines (e.g., benzylidene-methylamine). In other cases a twofold excess of Grignard reagent is recommended. The yields reported in Table XIX-II (reference II) are for one-to-one reactant ratio, and hence are not in most cases the maximum attainable.

Of the mechanism, or order, of the reaction nothing is known, but it seems probable that additions of this kind are essentially ionic.

References
Busch, Ber., 37, 2691-4 (1904).
Busch and Rinck, Ber., 38, 1761-72 (1905).
Busch and Leefhelm, j. Prakt. Chem., [2], 77, 20-5 (1907).
Campbell, Helbing, Florkowski & Campbell, JACS 70, 3868, (1948)
Moffett, JACS 69, 1792 (1947)

d) I seem to remember reading something similar to what Hex wrote but I can't remember where. i.e that CH3-CH=NCH3 aldimine is unstable. This also seems to be what was recommended in "Whole Drug Manufacturer's Catalog Transmittal by Chewbacca Darth", which may explain why the rxn was not found to work. So I guess you need to use phenylacetaldehyde-methylamine imine, unless you want to experiment with the more OTC route via acetaldehyde-methylamine imine. I would look up that acetaldehyde-methylamine imine in the "Dictionary of Organic Compounds", Beilstein, etc.

e) There was some discussion of this at the hive. I'm fairly sure people have tried it.
Back to top
IndoleAmine
Dreamreader Deluxe
Joined: 09 Feb 2005
Posts: 681
Location: Bahamas
18717.10 Points
View Single Post3632

 Mon Apr 18, 2005 12:47 am		 Reply with quote
I remember seeing somethingthat methylamine(g) was bubbled into acetaldehyde below 0°C and used directly in hope to avoid polymerization.

Does anyone know if it has helped actually?

Hex: I doubt that you can prepare the schiff base between any aldehyde and methylamine in a dean-stark apparatus at reflux temp. of benzene - the methylamine will mostly vaporize before it can react...


i_a
Back to top
Display posts from previous:   
Post new topic   Reply to topic    synthetikal.com Forum Index -> Misc. Stimulants All times are GMT + 5.5 Hours
Page 1 of 1

 



Powered by phpBB 2.0.11 © 2001, 2002 phpBB Group

Igloo Theme Version 1.0 :: Created By: Andrew Charron