Benzylamino group

More illustrative is the structure of the fluorosilane which exhibits the same tricapped tetrahedron geometry. The three N-Si interactions take place in the frontal position towards the Si-F bond instead of the rear coordination observed in penta- and hexacoordinated structures. Furthermore, the benzylamino groups have the possibility not to be coordinated at silicon since these groups have the capability of free rotation around the carbon-nitrogen bond. 

The direct sulfonadon of alkylaminotriphenylmethane dyes gives mixtures of substituted products. Although dyes containing anilino or benzylamino groups give more selective substitution, a sulfonated intermediate such as 3[(lV-ethy]-A-pheny]-amino)methy]]benzenesu]fonic acid (ethylbenzylanilinesulfonic acid) is the preferred starting material. 

Thus, one can conclude that the 3-benzylamino group in 311 g as well as ben-zylamine itself is oxidized into their corresponding imines easier than ordinary alkylamines. When both reactants do not contain a benzylamino fragment, the cyclohexylamino group is oxidized first. If both benzylamino and cyclohexylamino functions are absent in the reactants, the process starts from oxidation of a 3-alkylamino group as in 311e,f,k. Heterocyclizations described here represent a novel approach to condensed imidazoles and imidazolines. 

Sulfonation. The direct sulfonation of alkylaminotriphenylmethane dyes gives mixtures of substituted products. Although dyes containing anilino or benzylamino groups give more selective substitution, a sulfonated intermediate such as 3[(N-ethyl-N-phenylamino)methyl]benzenesulfonic acid (ethylbenzylanilinesulfonic acid) is the preferred starting material. However, Patent Blue V [354649-0], Cl Acid Blue 3, was made from 3-hydroxybenzaldehyde and two moles of diethyl aniline, followed by sulfonation of the leuco base and oxidation to the dye. FD C Green 2 [5141 -20-8/,... 

S,4/J,5/ )-/J-(./V-Acetylbenzylamino)-2,2,5-trimethyl-l,3-dioxolane-4-propanal can be prepared in a similar manner54 in 63% yield and with a diastereomeric purity of 90%, as determined by H NMR. Analysis of the H-NMR spectrum of the cyclization product obtained from this aldehyde by treatment with hydrochloric acid in anhydrous methanol unambiguously establishes the syn configuration of the vicinal hydroxy and benzylamino group. Thus, the stereochemical course of benzylamine addition to both 2-alkenylthiazolium salts is the same. 

Synthetic strategy for tetrahydroquinolinequinone 87 is similar to that for 63 (Scheme 11). Fusion with a piperidine ring at C-3/C-4 by introduction of hydroxypropyl and M-benzylamino groups at these sites, and subsequent cyclization by the Mitsimobu reaction (5 85) was followed by the usual... 

L1A1H ) of benzamldo-groups proceeds to give N-benzylamino-groups only in modest yield, but this transformation can be effectively performed if the group is N-allylated or N-silylated prior to reduction and de-N-protectlon. 

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