Synthetic Reductions in Clandestine Amphetamine and Methamphetamine Laboratories. Summary. A review of synthetic reductions utilized in the clandestine manufacture of amphetamine and methamphetamine is presented. General. discussions on the mechanism of heterogenous catalysis, dissolving metals, hydrides and non- metal reductions used in the manufacture. Introduction. This review addresses reductions in clandestine methamphetamine and amphetamine synthesis. Central to the diverse routes published for the. Of 9. 5 references surveyed concerning the.
Since such diversity exists in these approahes, we felt that. Secondly, we felt that a composite reference list would be of assistance in correlating notes or procedures found. Finally, two literature review articles in the forensic area have appeared and both. An overview of synthetic approaches to methamphetamine and amphetamine utilized reductive routes is outlined in Tables 1 and 2. Table 1 is organized by the type of catalytic surface or reductive species; i. Pd, Pt, Li. Al. H4, HCOOH etc. Table 2 is organized by the synthetic. Leuckart, Schiff base, oxime, nitrostyrene, etc. Figures 1- 1. 2 illustrate the chemical formulas of the chemical. Chemical Abstracts citations . Finally, the recurrent use of the terminology . Heagy, personal communication, from information gathered by attending clandestine laboratory sites. Heterogenous Catalysis. Year : Milestones : 2016 : Lupin Acquires Gavis Pharma in New Jersey. 2015 : Inaugurated a Center of Excellence for Inhalation Research in Coral Springs, Florida. This here is a cartoon I wrote for the Sarah Silverman show y’all! Same team as on all the short cartoons I wrote and directed for the Sarah show. The role of heterogenous catalytic hydrogenation and hydrogenolysis in organic synthesis is replete in the literature. However, the. mechanism of the catalyst's role has remained elusive due mainly to the difficulty of studying such heterogenous systems. Recent research. in this area has shown that a system charged with H2 and D2 in the prescense of a catalyst yields HD. This has been interpreted as the. H2 and weakening or disrupting of the H- H bond. Studies by Maier et al (pers. Furthermore, hydrogenation of an organic species (incapable of penetrating the Si. O2 layer) occurred. This suggests that coordination between the organic moiety and the catalytic surface may not be necessary. Further work in this area will be followed with interest. TETRABENAZIN (NITOMAN) BEI M. ZL-Reihenuntersuchung Schnell freisetzende Gabapentin-600-mg-Filmtabletten im Vergleich. Von Astrid Kaunzinger, Petra Gr Ik word als scheikundige en iemand met een interesse in psychoactieve drugs vaak gevraagd of ik de serie Breaking Bad kijk, en of de show een goede weergave is van. Heterogenous catalytic hydrogenation of ephedrine to methamphetamine in clandestine laboratories is often achieved with palladium. Adams catalysis) is second in frequency. Fig 1). Similar correlations apply to the reduction of phenylpropanolamine. Raney Nickel. Hydrogenolysis of ephedrine or phenylpropanolamine (here hydrogenolysis is defined as reduction of C- X) is not a result of reduction of the. OH bond. The actual moiety reduced is C- X, where X refers to the halogen. Fig 1). This moiety (C- X) may be produced in situ. The stereochemistry and analytical methology for methamphetamine prepared from ephedrine and pseudoephedrine has. Heterogenous catalysis has been used to reduce the imine bond of Schiff bases formed with phenyl- 2- propanone and ammonia or methylamine in. Fig 2). When heterogenous catalysis is utilized in this Schiff. P2. P reduction to 1- phenyl- 2- propanol, limits the yield of amphetamine or methamphetamine. This has limited. H for the Schiff's bases is between 6 and 7. Other clandestine routes, although less popular, which have open literature references utilizing heterogenous catalysis for the synthesis. Fig 3), nitrostyrene reduction. Fig 4), 2- keto- oxime reductions. Fig 5) and hydrazone reduction. Fig 6). Precursors to amphetamine (phenylpropanolamine) and methamphetamine (ephedrine) have been synthesized with the aid of heterogenous catalysis. Fig 5). Dissolving Metal Reductions. Dissolving metal reductions, in particular aluminum, continue to be the most popular synthetic route to methamphetamine and amphetamine in. United States. Although molecular H2 is produced as the metal dissolves, this is generally considered a. The actual reduction mechanism does not involve molecular H2, but is, in fact, a result. Electron transfer from the metal to a heteroatom results in a radical carbon, which abstracts. In metals where higher oxidation states are present (i. Al, Mg, Zn) dimers may form as a. Poisoning of catalysis in one approach used to minimize rapid dissolution of the metal and to abate evolution of H2. Amalgams made between. This popularity persists despite US Government. Schedule II) of P2. P in 1. 98. 0. This controlled status has resulted in an upsurge in the clandestine manufacture of P2. P. A variey of. synthetic routes have surfaced in clandestine laboratories, primarily through phenylacetic acid. Fig 7). Alternatives to the. P2. P have appeared. One approach to P2. P utilizes a. dissolving metal reduction of nitrostyrene with iron and hydrochloric acid. Fig 4). Clandestine laboratories which utilize other dissolving metal reduction routes have been infrequently encountered. However, reduction of a. Schiff base to methamphetamine. Fig 2) and of 5- phenyl- 4- methylthiazole to amphetamine. Fig 8 ) using sodium in alcohol are cited in. Additionally, Na/alcohol reduction of an oxime. Fig 3), Na/Hg amalgam reduction of a nitrostyrene. Fig 4). or a 2- keto- oxime. Fig 5) to amphetamine and Zinc/HCl reductions of chloro analogs of ephedrine to methamphetamine. Fig 1) are. also cited in the literature. Metal Hydride Reductions. Metal hydride reductions have not captured the imagination of clandestine laboratory chemists like the remainder of the scientific community. Metal hydrides function by transfer of a hydride ion to the electron- deficient center (typically carbon) of a. Protonation is effected on the electron- rich center via the solvent media in case of Na. BH4 or product workup in the case of Li. Al. H4. The infrequent use of metal hydride reducing agents in cannot be attributed to the lack of open literature references in these agents. Unfortunately, the activity of Na. BH4 is sufficient to reduce the ketone of P2. P, and. this is a competing reaction. This is not the case with the more selective reducing agent Na. BH3. CN whose activity is dependent upon the p. H. of the reaction media. Lithium aluminium hydride, whose activity is greater and therefore less selective than Na. BH4 has been used to. Sodium borohydride has also been used in a. Fig 1. 25. 6. Non- metal Reductions. Non- metal reductions to amphetamine and methamphetamine have been what might be termed as . In the early and mid 1. Leuckart synthesis, which employs formic acid, was the polular clandestine route to. For whatever reason, this route, which is still very common in Western Europe, lost popularity in the. United States by the end of the 1. In the early 1. 98. Southwestern and Western areas of the United States. Although several literature references link the Leuckart synthesis. Fig 9) to amphetamine. Fig 1). Several general benzylic alcohols have been reduced to their aliphatic. It seems clear that the benzylic alcohol of. However, the mechanism of the carbon- halogen reduction is inconjecture; i. Conclusion. In this review we have addressed reductive approaches to amphetamine and methamphetamine via heterogenous catalysis, dissolving metals. The chemistry of these varied approaches has been highlighted with emphasis on the role of the. It may be concluded that there are many options available to clandestine chemists (see Fig 1- 1. However, in actual. United States are: The aluminum foil reduction of the Schiff base adduct of P2. P and methylamine. The palladium catalyzed reduction of the chloro analog of ephedrine to methamphetamine. The hydriodic acid reduction of ephedrine to methamphetamine.
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