Aluminum Ephedrine

Propiophenone. Propiophenone [93-55-0] (ethyl phenyl ketone) is a colorless Hquid with a flowery odor. It can be prepared by the Friedel-Crafts reaction of benzene and propionyl chloride in the presence of aluminum chloride (346), or by the catalytic reaction of benzoic acid and propionic acid in the presence of water (347). Propiophenone is commercially available (348), and is sold in Japan at 2700 Y/kg (349). It is used in the production of ephedrine, as a fragrance enhancer, and as a polymerization sensitizer. 

Acylation of norephedrine (56) with the acid chloride from benzoylglycolic acid leads to the amide (57), Reduction with lithium aluminum hydride serves both to reduce the amide to the amine and to remove the protecting group by reduction (58), Cyclization by means of sulfuric acid (probably via the benzylic carbonium ion) affords phenmetrazine (59), In a related process, alkylation of ephedrine itself (60) with ethylene oxide gives the diol, 61, (The secondary nature of the amine in 60 eliminates the complication of dialkylation and thus the need to go through the amide.) Cyclization as above affords phendimetra-zine (62), - Both these agents show activity related to the parent acyclic molecule that is, the agents are CNS stimulants... 

The oxazaborolidines are easily prepared by heating ephedrine with borane dimethyl sulfide or the appropriate boronate ester. The aluminum reagent C is obtained by mixing ephedrine and trimethylaluminum. Borolidinc A is superior to its methyl derivative B and to the aluminum analog C. The diastereomeric borolidine obtained from borane and (S,S)-pseu-doephedrine failed to show any cnantioselectivity25. A variety of aromatic aldehydes can be enantioselectively alkylated in the presence of A, however, with heptanal the enantioselectivity is poor25. 

Incompatibilities of anionic emulsifying wax are essentially those of sodium alkyl sulfates and include cationic compounds (quaternary ammonium compounds, acriflavine, ephedrine hydrochloride, antihistamines, and other nitrogenous compounds), salts of polyvalent metals (aluminum, zinc, tin, and lead), and thioglycollates. Anionic emulsifying wax is compatible with most acids above pH 2.5. It is also compatible with alkalis and hard water. 

Lithium aluminum hydride-1-)-N-Methyl-ephedrine, 238 Lithium arenesulfonates, 69 Lithium benzeneselenOlate, 238-239 Lithium bis(ethylenedioxyboryl)methide,... 

An amino alcohol (lS,2/ )-8 consisting of ephedrine and proline units was constructed by forming the amide of tV-benzyloxycarbonylproline with ephedrine and reducing it with lithium aluminum hydride to the corresponding amino alcohol14, l 5. 

By comparison to peroxides, the azo compounds are generally not susceptible to chemically induced decompositions. It was shown,however, that it is possible to accelerate the decomposition of a,a -azobisisobutyronitrile by reacting it with bis(-)-ephedrine-copper(II) chelate. The mechanism was postulated to involve reductive decyanation of azobisisobutyronitrile through coordination to the chelate. Initiations of polymerizations of vinyl chloride and styrene with a,a -azobisisobutyronitrile coupled to aluminum alkyls were investigated. Gas evolution measurements indicated some accelerated decomposition. Also, additions of large amounts of tin tetrachloride to either a,a -azobisisobutyronitrile or to dimethyl-a,a -azobisis-obutyrate increase the decomposition rates. Molar ratios of [SnCl4]/[AIBN]= 21.65 and [SnCl4]/[MAIB] = 19.53 increase the rates by factors of 4.5 and 17, respectively. Decomposition rates are also enhanced by donor solvents, like ethyl acetate or propionitrile in the presence of tin tetrachloride. ... 

---