A Phenylethylamine

Deamination, Transamination. Two kiads of deamination that have been observed are hydrolytic, eg, the conversion of L-tyrosiae to 4-hydroxyphenyUactic acid ia 90% yield (86), and oxidative (12,87,88), eg, isoguanine to xanthine and formycia A to formycia B. Transaminases have been developed as biocatalysts for the synthetic production of chiral amines and the resolution of racemic amines (89). The reaction possibiUties are illustrated for the stereospecific synthesis of (T)-a-phenylethylamine [98-84-0] (ee of 99%) (40) from (41) by an (5)-aminotransferase or by the resolution of the racemic amine (42) by an (R)-aminotransferase. 

Diaziridine (33) was obtained with more than 90% optical purity by separation of the a-phenylethylamine salts (76IZV1898). 

The present procedure was developed from those of Wallach and Freylon, based upon the general method discovered by Leuckart. a-Phenylethylamine also can be prepared satisfactorily by the reduction of acetophenone oxime with sodium and absolute alcohol or sodium amalgam, but the reagents are more expensive and the processes less convenient. The amine has been obtained by reducing acetophenone oxime electro-lytically, by reducing acetophenone phenylhydrazone with sodium amalgam and acetic acid, from a-phenylethyl bromide and hexamethylenetetramine, and by the action of methyl-magnesium iodide upon hydrobenzamide, as well as by other methods of no preparative value. 

The purity of (/-a-phenylethylamine-/-malate is not readily determined by its melting point or specific rotation, but rather by its massive crystalline form and solubility. The acid and neutral /-base-/-acid salts are much more soluble, and usually do not crystallize at all. 

By the method referred to under the benzyl/soquinoline alkaloids (p. 193) Leithe has shown that the configuration of the I- and d-canadines by reference to Z( —)-a-phenylethylamine is l(—) and d(-j-) respectively. 

In another example of enantioselective distillation, it was the enantiomeric mixture to resolve itself which contributed to create a chiral environment. Thus, non-racemic mixtures of a-phenylethylamine were enantiomerically enriched by submitting to distillation different salts of this amine with achiral acids [199]. 

L-Pkenylalanine, reaction with phthalic anhydride to yield N-phthalyl-L-phenylalanine, 40,82 Phenyl terf-BUTYL ether, 41, 91 a-Phenylethylamine, N-chlorination of, 41,82... 

Among the amines that have been resolved with (-)-DAG are a-phenylethylamine (a-methylbenzenemethanamine),s [R-(R, R )]-2-amino-l-(4-nitrophenyl)-l, 3-propanediol,61,2,3,4,5,6,7,8-octahydro-l-(4-methoxyphenylmethyl)isoquinoline, 3-methoxymorphinan, 1,2,3,4-tetrahydro-7-methoxy-4-phenylisoquinoline, 3-hydroxy-A7-methyl-... 

The asymmetric Diels-Alder addition is a powerful tool of organic chemistry therefore, its variant using diaza dienophiles has also been studied. When chiral diene 562, derived from (A)-phenylethylamine, is allowed to react... 

The methods for preparation of a-phenylethylamine are reviewed in Org. Syn. Coll. Vol. 2, 1943, 506, where detailed directions are given for the preparation of this amine from acetophenone and ammonium formate. The procedure given above is based upon that of Schwoegler and Adkins.1... 

The presence of ammonia in the reduction mixture reduces the amount of secondary amine formed. For directions for introducing the liquid ammonia, see Note 1 to the preparation of a-phenylethylamine (p. 69). 

---