Diphenylethylamines

N-methyl-l,2-diphenylethylamine, 34, 64 tetraphenylarsonium chloride hydrochloride, 30, 97 Guanidine, 32, 96 Guanidine hydrochloride, 32, 45 Guanylthiourea, 35, 69 D-GuLONIC ACID, y-LACTONE, 36, 38... 

Irradiation of an equimolar mixture of t-S and DCNB in 9 1 acetonitrile-water solution containing ammonia results in the formation of 1,2-diphenylethylamine in 46% yield106. 

C. N-Methyl-, 2-diphenylethylamine hydrochloride. Hydrogen chloride gas (Note 4) is passed into a stirred solution of 30 g. (0.14 mole) of N-methyl-l,2-diphenylethylamine in 500 ml. of anhydrous ether until saturated or until a drop of the ether on moistened pH test paper indicates that it is strongly acid. The hydrochloride separates as a colorless crystalline precipitate. It is collected on a suction filter, washed with ether, and dried. The yield is 34.2-35.1 g. (97.5-100%), and the product is practically pure, m.p. 184-186°. If desired it can be recrystallized by dissolution in a little methanol followed by addition of absolute ether. 

For the preparation of N-methyl-l,2-diphenylethylamine it is not absolutely necessary to distil the N-benzylidenemethyl-amine. The dried benzene solution can be used directly. 

N-Methyl-l,2-diphenylethylamine has been prepared in 8% yield by the Leuckart reaction from desoxybenzoin and methyl-ammonium formate 8 and by the present method.9... 

Ph-CH )-CH(NH3)-Me HS04 ] with copper(n) nitrate was more successful in that the (S)-( —)-enantiomer (15) was formed in 85 per cent chemical yield and 95 per cent optical purity.6 (S)-( — )-10,10 -Dihydroxy-9,9 -biphenanthryl has been similarly prepared from the coupling of 9-phenanthrol, using (R)-( —)-1,2-diphenylethylamine and copper(n) nitrate.7 Enantioselective syntheses of... 

Substituted a-nitrostilbenes were hydrogenated to 1,2-diphenylethylamines in 52-87% yields, conveniently in methanol over in situ-prepared Pd-C catalyst (eq. 9.28).53 In these cases the hydrogenation was carried out in presence of the hydrogen chloride formed from palladium chloride, the amount of which, however, was much smaller (-0.0022 mol) for the nitrostilbenes hydrogenated (0.037-0.042 mol). In one instance, a-nitro-4 -methoxystilbene gave rise to a small amount of the corresponding oxime when the hydrogen uptake was less than theoretical. 

Glyoxal-sodium bisulfite, 30, 86 GlYOXYLIC acid, n-BUTYL ESTER, 35, 18 ETHYL ESTER, DIETHYL ACETAL, 35, 59 Grignard reaction, addition to ethyl sec-butylidenecyanoacetate, 35, 7 allylmagnesium bromide with o , 8-di-bromoethyl ethyl ether, 36, 61 allylmagnesium chloride with a,/3-di-bromoethyl ethyl ether, 36, 63 ethylmagnesium bromide with tin tetrachloride, 36, 86 N-methyl-l,2-diphenylethylamine,... 

S)-( - )-10,10 -Dihydroxy-9,9 -biphenanthryl (l). The reagent is obtained by oxidative coupling of 9-phenanthrol in the presence (R)-l,2-diphenylethylamine with Cu(N03)2 3H20. 

Preparative Methods racemic l,l -bi-2,2 -naphthol (BINOL) is most conveniently prepared by the oxidative coupling reaction of 2-naphthol in the presence of transition metal complexes (eq 1). The resolution of racemic BINOL with cinchonine may be performed via the cyclic phosphate (eq 2). An alternative procedure to provide directly optically active BINOL is the oxidative coupling of 2-naphthol catalyzed by Cu salt in the presence of chiral amines (eq 3). The best procedure uses (+)-amphetamine as the chiral ligand and provides BINOL in 98% yield and 96% ee. Above 25 °C the Cu /(+)-amphetamine/(5)-BINOL complex precipitates, while the more soluble Cu /(+)-amphetamine/(I )-BINOL complex is slowly transformed into the former complex. 9,9 -Biphenanthrene-10,10 -diol has also been prepared in 86% yield and with 98% ee by a similar asymmetric oxidative coupling of 9-phenanthrol in the presence of (I )- 1,2-diphenylethylamine. ... 

Optical rotatory dispersion (ORD) spectra have also been used to assign absolute configiu-ation to these alkaloids. (— )-Tetrahydro-palmatine (XLI) exhibits a negative Cotton effect in the region of 300 mp. and this has been correlated with the representation of its absolute configuration as 14 R on the basis of a comparison with the positive plain dispersion curve shown in this region by (+ )-l,2-diphenylethylamine (XLIX) (97). 

In the reviewer s opinion, the simple diphenylethylamine, with its greater degree of flexibility, does not really constitute a suitable model for such a correlation to be made with any degree of confidence. 

N-Methyl-1,2-diphenylethylamine AND HYDROCHLORIDE, 34, 64 2-Methyldodecanoic acid, 38, 43, 47, 49 2-Methyl-2-dodecenoic acid, 38, 49,50 trans-2-Methyl-2-dodecenoic acid,... 

Diethylproprion is a diphenylethylamine compound which promotes the release of noradrenaline (and to lesser extent, dopamine) from presynap-tic neurones. It was introduced into clinical practice for the treatment of obesity over 40 years ago. A number of clinical trials have shown it to be significantly more effective than placebo, although less effective than phentermine or mazindol, in helping obese patients lose weight. As noted above, it does not lead to tolerance. Side effects are mild. Some patients experience mild stimulant symptoms and tachycardia. The risk of dependence has proved to be low. 

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