2-Phenylethyl amine

The aqueous acid solution is transferred to a i-l. round-bottomed flask provided with a separatory funnel and equipped for steam distillation. A solution of 125 g. of sodium hydroxide in 250 cc. of water is added through the funnel, and the mixture is distilled with steam (Note 4). The first liter of distillate contains most of the amine, but the distillate should be collected until it is only faintly alkaline. A small residue containing di-(a-phenylethyl)-amine and neutral substances remains in the flask and may be discarded. 

Utilizing the Zincke reaction of salts such as 112 (Scheme 8.4.38), Binay et al. prepared 4-substituted-3-oxazolyl dihydropyridines as NADH models for use in asymmetric reductions. They found that high purity of the Zincke salts was required for efficient reaction with R-(+)-l-phenylethyl amine, for example. As shown in that case (Scheme 8.4.38), chiral A-substituents could be introduced, and 1,4-reduction produced the NADH analogs (e.g. 114). 

The exchange of the chiral phenylethyl amine against an optically active amino acid fragment 269 allowed the synthesis of conformationally restrained dipeptidyl lactams 271 and 272 including the so called Freidinger lactams as... 

The amidase from Rhodococcus erythopolis strain MP50 was nsed to selectively convert racemic 2-phenylpropionamide into 5 -2-phenylpropiohydroxamate. This was converted into the isocyanate by Lossen rearrangement and then by hydrolysis to S-( )-phenylethyl-amine (Hirrlinger and Stolz 1997). 

Figure 3 presents the mean levels of self-infusion for the 14 phenylethyl-amines shown in figure 1. Of all the drugs tested, injection rates were... 

Zincate reagents can add to imines with or without Lewis acid catalysis. Alkylimines require BF3 but imines of pyridine-2-carboxaldehyde react directly. If the imines are derived from chiral amines, diastereoselectivity is observed. Both a-phenylethyl amine and ethyl valinate have been tried. Higher enantioselectivity was observed with mixed magnesium reagents.175... 

In order to explore the generality of this new domino reaction the conversion of various primary amines with 2-341 and the cyclohexane analogue was investigated (Scheme 2.81). For example, the reaction proceeds with high yields when benzyl- or (2-phenylethyl)amine are used (entries 1 and 2). In comparison, sterically more hindered amines such as 2-butylamine produced much lower yield (entry 4) Furthermore, the reaction tolerates other functional groups, such as an unprotected hydroxyl group (entry 5), and variation of the enone ring size is possible (entries 6 and 7). More recent results have revealed that the addition of Sn(OTf)2 or In(OTf)2 makes the transformation more reliable. 

If several runs are made, a small amount of the secondary-amine may be recovered from the combined residues. Di-(/3-phenylethyl)-amine boils at 155-157°/4 mm. 

The linkage of uptake to the Na+ gradient may be of physiological significance since transport temporarily ceases at the time of depolarization-induced release of catecholamines. The transport of catecholamines can be inhibited selectively by such drugs as tricyclic antidepressants and cocaine. In addition, a variety of phenylethyl-amines, such as amphetamine, are substrates for carrier thus, they can be concentrated within catecholamine-containing neurons and can compete with the catecholamines for transport. 

Hwang, E. C., and Van Woert, M. H. (1980) Comparative effects of substituted phenylethyl-amines on brain serotonergic mechanisms. J. Pharmacol. Exp. Ther., 213 254-260. 

Baker GB, Nazarali, AJ, Coutts RT. 1985. A rapid and sensitive procedure for the simultaneous analysis of p-phenylethyl-amine and tranylcypromine in rat brain using trichloro-acetylation and gas chromatography. Res Commun Chem Pathol Pharmacol 5 317. 

A breakthrough was achieved with chiral phosphoramidite (S, R, i )-18, in which a C2-symmetric (S)-binaphthyl unit and a C2-symmetric (R, R)-bis-(l-phenylethyl)-amine unit are present (Scheme 7.10), resulting in the enantioselective catalytic 1,4-addition of Et2Zn to 2-cyclohexenone (6) with >98% ee [38]. 

The vinyloxirane reaction was later extended to methylidene cyclohexene oxide and to related meso derivatives [53]. The effects of the diastereomeric ligands 42 and 43 (Fig. 8.5), derived from (S)-binaphthol and (S, S)- or (R, R)-feis-phenylethyl-amine respectively, were investigated. In the case of kinetic resolution of racemic methylidene cyclohexane epoxide 45 with Et2Zn, ligand 42 produced better yields, regioselectivity, and enantioselectivity than 43 (Scheme 8.27). 

Table 3 Enantioselective hydrogenation of N-(l-phenylethylidene)aniline (8) to (Biphenyl-(1-phenylethyl) amine (9) in IL/CO2 systems ...

Figure 1 shows the X-ray crystal structure of the (R)-(+)-l-phenylethyl-amine salt of keto-acid 37a prior to reaction and following 70% conversion to the corresponding cyclobutanol 38b. The structure of the mixed crystal is... 

For reliable quantification, the deuterium-labelled substrate (ds-phenylethyl-amine) was added to the matrix as internal standard. To circumvent the problem of crystal inhomogenities, 100 acceptable spectra were measured from seven to ten different positions of one sample spot and averaged. The MALDI-MS assay was validated with a gas chromatography-based quantification scheme and was found to be in good compliance. This methodology obviously allows a reliable quantification of the low molecular weight analytes of interest. Nevertheless, the need for isotopically labelled compounds as internal standards is still a bottleneck, as these are usually rather expensive or have to be laboriously synthesized. 

Although this drug is categorized as a local anesthetic, I have chosen to put it in with the hallucinogens because of the psychotomimetic effects that it produces. Cocaine is not a phenylethyl-amine, but it produces central nervous system arousal or stimulant effects which closely resemble those of the amphetamines, the methylenedioxyamphetamines in particular. This is due to the inhibition by cocaine of re-uptake of the norepinephrine released by the adrenergic nerve terminals, leading to an enhanced adrenergic stimulation of norepinephrine receptors. The increased... 

Procedure for KR of an a-chiral primary amine using catalyst 17 KR of( )- 1-phenylethyl-amine [99]... 

The reaction shown in Scheme 39 was also performed starting from a chiral carbamoyl chloride (91, Y = O) derived from (f )-iV-methyl-iV-(l-phenylethyl)amine, in order to study the possible asymmetric induction using prochiral carbonyl compounds. Thus, with pivalaldehyde or benzaldehyde the mixture of diastereomers obtained was ca 1 1. This behavior was also observed with other chiral functionalized organolithium compounds ". ... 

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