Crystalline derivatives preparation amines, primary

The above reactions wiU serve to place an amine into its class— primary, secondary or tertiary. For complete characterisation, a crystalline derivative should be prepared. A large number of derivatives of amines are avaUable the foUowing wiU be found useful. 

Reaction of various primary amine-terminated dendrimers with either inorganic or organic acids allows the preparation of a wide variety of crystalline derivatives. One such intermediate was implicated in the development of lyotropic phases [156] when octanoic acid was combined with Starburst poly(ethylenimine) (generation-3). 

The diethyl compound without the iodine is 2,5-dimethoxy-N,N-diethylamphetamine, which was prepared by the reductive alkylation of DMA with acetaldehyde and sodium cyanoborohydride. This product, DEDMA, was a clear white oil, bp 82-92 °C at 0.15 mm/Hg which did not form a crystalline hydrochloride. An interesting measure of just how different these N,N-dialkylated homologues can be from the psychedelic primary amines, pharmacologically, can be seen in the published report that the beta-hydroxy derivative of DEDMA is an antitussive, with a potency the same as codeine. 

Secondary amines can be prepared from the primary amine and carbonyl compounds by way of the reduction of the derived Schiff bases, with or without the isolation of these intermediates. This procedure represents one aspect of the general method of reductive alkylation discussed in Section 5.16.3, p. 776. With aromatic primary amines and aromatic aldehydes the Schiff bases are usually readily isolable in the crystalline state and can then be subsequently subjected to a suitable reduction procedure, often by hydrogenation over a Raney nickel catalyst at moderate temperatures and pressures. A convenient procedure, which is illustrated in Expt 6.58, uses sodium borohydride in methanol, a reagent which owing to its selective reducing properties (Section 5.4.1, p. 519) does not affect other reducible functional groups (particularly the nitro group) which may be present in the Schiff base contrast the use of sodium borohydride in the presence of palladium-on-carbon, p. 894. 

The most comprehensively studied Mn" Schiff base compounds are those of the quadridentate hybrid O—N—N—O donor set ligands of structure (161) the ligand salenH2 (161) where Y = H and X = (CH2)2) being the object of a number of different studies.389,418 The orange-yellow, crystalline, air-stable compound [Mn(salen)(en)J was isolated in 1933 and shown to rapidly oxidize in solution.419 The compound [Mn(salen)] has been prepared by the four main methods used to prepare metal compounds of ligands derived from the interaction of salicylaldehydes and primary amines,420 these are ... 

JCS(P1)1171] and Sung (81CC1089 82JOC3623) found that these 1,2,4-triazole derivatives of uridine can be readily prepared at room temperature with excess 1,2,4-triazole and phosphoryl chloride and triethylamine or with 0-chlorophenyldi-(l//-l,2,4-triazol-l-yl)phosphine oxide in acetonitrile. These stable, often crystalline 1,2,4-triazole derivatives react readily with aqueous ammonia and primary or secondary amines at room temperature to afford the corresponding cytidines in high yields. 

For the identification and subsequent characterization of hydroxy compounds as well as primary and secondary amines, by preparing their crystalline acetyl derivatives. 

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