Benzylamine, 2,3-dimethoxy

Benzyl alcohol, o-methyl-, 34, 58 Benzylamine, 35, 91 Benzylamine, 2,3-dimethoxy-N-methyl, 30, 59 N,N,o-trimethyl-, 34, 61... 

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. 

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. 

An interesting reaction has been described by Simonov and his colleagues [371], Studying the reaction of some aromatic rnt/zo-dinitro- and trinitrocompounds with benzylamine they have discovered that under special conditions the reaction of substitution of the nitro group with the benzylamine group is accompanied by reduction of the second nitro group and cyclization into 2-phenylbenzimidazole derivatives. In this case benzyl alcohol forming from benzylamine serves as a reducer. By the way it was obtained 4,5-dimethoxy-7-nitro-2-phenylbenzimidazole in 89% yield from 3,4,5-trinitroveratrole [371],... 

The allylic amination with benzylamine or related amines such as (3,4-dimethoxy-phenyl)methylamine catalyzed by palladium coordinated with the dihydroxylated ferrocenylphosphine 8b takes place with high enantioselectivity (Scheme 2-30) [27]. Thus, reaction of l,3-diphenyl-2-propenyl ethyl carbonate 41 with benzylamine gives a quantitative yield of allylic amination product 42 with > 97% ee. High enantioselectivity is also obtained in the allylic amination of 2-propenyl esters 43 substituted... 

Recently, Carreira and coworkers have utilized CIC Iz in their U-4CR for the rapid synthesis of the core fragment of Orodin alkaloid Massadine (252, Figure 7.6), which was isolated from Stylissa aff Massa [91]. Reaction of norbomenone (9v), 2,4-dimethoxy benzylamine (DMB-NH2, 6y), p-TsOH, and Iza provided the acyclic Ugi product 256 in a 79% yield. Removal of DMB group, Boc protection, and reduction, followed by treatment of -amylnitrile afforded the IV-acylbenzotriazole intermediate 257. Borohydride reduction of 257 provided alcohol 258. After several steps, the suitably substituted o-ring 259 of Massadine (252) was provided (Scheme 7.79) [91]. 

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