Benzylamine, «-methyl

A mixture of 23.8 grams (0.2 mol) of propargyl bromide, 24.2 grams (0.2 mol) of N-methyl benzylamine and 400 ml of anhydrous ethanol in the presence of 42.4 grams (0.4 mol) of anhydrous sodium carbonate was heated at the boiling temperature and under reflux for a period of 17 hours. 

More recently, other substituted benzylidene derivatives of the enantiomers of a-methyl-benzylamine have been converted with substituted benzaldehydes to the corresponding phenyl-glycinonitriles using sodium cyanide in aqueous methanol44. 

Analog erhalt man aus 4-Methyl-benzoesaure-nitril 4-Methyl-benzylamin (63% d.Th.). 

Dioxo-4,8-diphenyl-l,3,5,7-tetraaza-bicyclof3.3.0]octan laBt sich durch Lithium-alanat in5-Hydroxy-3- phenyl-1,2,4- triazolidin (14% d.Th.), N-Methyl- benzylamin auf-spalten4 ... 

Later on the crucial role played by the solvent was enlightened in the protease-catalyzed resolution of racemic amines [26]. As shown in Table 1.3, the ratio of the initial rates of acylation of the (S)- and the (Ji)-enantiomers or racemic a-methyl-benzylamine (9) varied from nearly 1 in toluene to 7.7 in 3-methyl-3-pentanol. Similarly, the same authors found a significant solvent effect for the subtilisin-catalyzed transesterification of racemic 1-phenylethanol (10) using vinyl butyrate as acyl donor (Table 1.4 [27]). 

Having explored the scope of this reaction, it was then possible to use an optically active phosphoramidate (232.d), derived from (5)-a-methyl-benzylamine, to perform a kinetic resolution procedure.134,138 Upon reaction of 221 with 0.5 equiv of the phosphoramidate anion 232.d, selective reaction with the 7 -isomer of 221 resulted in an enhancement in the proportion of 5-221 along with the expected ketenimine products (233). The absolute configuration of i -233.d was determined by X-ray crystallography, and thus all other absolute configurations assigned by comparison of CD and HPLC data.39,138... 

The synthesis and purification of C12BMG by the reaction of N-methyl-benzylamine with sodium chloroacetate followed by the quaternization of the resulting tertiary ammonioacetate with 1-bromododecane is described elsewhere (12). Purification of aqueous solutions of the surfactant for surface tension measurements and determination of the surface tension of the solutions by the Wilhelmy method using a sandblasted platinum blade were by techniques previously described (13). The concentration of C12BMG in aqueous solution was determined by measuring its absorbance at 263 nm (e = 350.5). 

Das Imin I [aus Glyoxylsaure-ethylester und (L)-a-Methyl-benzylamin] addiert das Uber-gangsmetall zu diastereomeren Imin-Addukten II und III (im Verhaltnis 1 9), die getrennt stereoselektiv von Alkylbromiden reduktiv zu (R)-Aminosauren alkyliert werden (77-95%ee). Aus dem (D)-Amin erhalt man entsprechend die (.S )-Aininosaure5. 

Die optisch-aktiven a-Methyl-benzylamine cyclisieren mit erythro- oder t/izeo-2,3-Dibrom-butansaure-estern zu den entsprechenden chiralen (1R)- bzw. (75)-2,3-/ra s-Dimethoxy-carbonyl-l-(l-phenyl-ethylamino)-aziridinen. Sie werden katalytisch zu (S)- bzw. (R)-As-paraginsaure hydriert und verseift13. 

This NMR technique has been applied to a series of alkanediammonium ions, and the results (induced shifts of proton resonances) are summarized in Fig. 2. It may be seen that the shielding region extends for approximately 4.5 methylene units, or 6 A, which coincidentally is the interatomic distance axially spanning the cavity of cucurbituril. Similar induced chemical shift effects are found in CNMR spectra, and UV spectral perturbations are noted upon encapsulation of certain aromatic-ring bearing ammonium ions (particularly 4-methyl-benzylamine). Conclusive evidence for internal complexation with cucurbituril has been secured by crystallography [3]. 

Reduction of the complex on Raney nickel yielded benzylamine, N-methyl-benzylamine, and N,N-dimethylbenzylamine but no / -phenylbenzylamine, a reduction product resulting under the same reaction conditions from benzyl cyanide. Hydrolysis with dilute sulfuric acid in acetic acid yielded benzylamine only, and oxidation of the complex with potassium permanganate gave 4.2 moles of benzoic acid per mole of complex. The bromide anion can be exchanged metathetically with various other anions such as perchlorate, iodide, and thiocyanate. When heated at 100° C. in vacuum, the complex lost one mole of benzyl bromide and yielded only one dicyanotetrakis(benzylisonitrile)iron(II) complex. 

Second, the asymmetric induction in hydroformylation at room temperature is in the range of that observed in the formation of cis-a- [methyl-benzylamine] - [olefin] -dichloroplatinum (II) complexes after reaching... 

Unprotected racemic amines can be resolved by enantioselective acylations with activated esters (110,111). This approach is based on the discovery that enantioselectivity of some enzymes strongly depends on the nature of the reaction medium. For example, the enantioselectivity factor (defined as the ratio of the initial rates for (5)- and (R)-isomers) of subtilisin in the acylation of a-methyl-benzylamine with trifluoroethyl butyrate varies from 0.95 in toluene to 7.7 in 3-methyl-3-pentanol (110). The latter solvent has been used for enantioselective resolutions of a number of racemic amines (110). 

The optical isomers of DOM have been prepared in two ways. The racemic base has been resolved as the ortho-nitrotartranilic acid salt by recrystallization from EtOH. The (+) acid provides the (+) or S isomer of DOM preferentially. Also, the above-mentioned l-(2,5-dimethoxy-4-methylphenyl)-2-propanone can be reductively aminated with optically active alpha-methyl benzylamine with Raney Nickel. This amine is isolated and purified by recrystallization of the hydrochloride salt. When optically pure, the benzyl group was removed by hydrogenolysis with palladium on carbon. The mp of either of the optical isomers, as the hydrochloride salts, was 204-205 °C. 

The procedure is illustrated in Expt 5.219 by the resolution of ( )-a-methyl-benzylamine (1-phenylethylamine) with the aid of tartaric acid. 

N-Benzyl-2-bromo-N-methyl-benzamide (35). A suspension of morpholine resin (3, 0.63 mmol) in DCM (2 ml) was treated with. V-methyl-benzylamine (0.23 mmol) and 2-bromobenzoyl chloride (0.146 mmol). The reaction mixture was shaken for 5 h. Isocyanate resin (15, 0.2 g) was added followed by DCM (1 ml). The reaction mixture was then shaken for 16 h. Filtration of the resin followed by concentration of the filtrate gave the purified product. 

Enantiopure acetal 237 and a-methyl benzylamine 238 were mixed in methanol in the presence of tert-butyl isocyanide and benzoic acid to afford a separable diastereomeric mixture of the Ugi reaction 4CR product 239. Debenzylation using... 

To the solution of 16.2 g thereof in 450 ml of ethanol, 14.10 g of N-methyl-benzylamine are added and the mixture is refluxed for 3 hours. It is evaporated, the residue taken up in methylene chloride, the solution washed with saturated aqueous sodium carbonate dried, filtered and evaporated. The residue is triturated with diethyl ether, to yield the l-(o-nitrobenzyl)-2-(N-methyl-N-benzylaminoacetyl)pyrrole. 

Figure 18.19. Dynamic kinetic resolution of a-methyl benzylamine (60).

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