Benzylamine hydrazone

In the discussion of benzylamines, we have met medicinal agents that owe their activity to some particular functionality almost without reference to the structure of the rest of the molecule. The hydrazine group is one such function in that it frequently confers monamine oxidase-inhibiting activity to molecules containing that group. Such agents frequently find use as antidepressants. Thus, reduction of the hydrazone of phenyl-acetaldehyde (84) affords the antidepressant phenelzine (85). Similar treatment of the derivative of phenylacetone (86) gives pheniprazine (87). ... 

Aldoximes yielded primary amines by catalytic hydrogenation benzaldehyde gave benzylamine in 77% yield over nickel at 100° and 100 atm [803, with lithium aluminum hydride (yields 47-79%) [809, with sodium in refluxing ethanol (yields 60-73%) [810] and with other reagents. Hydrazones of aldehydes are intermediates in the Wolff-Kizhner reduction of the aldehyde group to a methyl group (p. 97) but are hardly ever reduced to amines. 

Silylation of benzyl C-H bonds using hydrosilanes can also be performed with the aid of Ru3(CO)12-catalyst (Table 1) [9]. This silylation occurs only at benzylic CH3 groups. Pyridine, pyrazole, and hydrazones function as good directing groups. Benzylamines, oxime ethers, dimethylanilides, and aryl pyridyl ethers have no activity in this silylation. 

The semicarbazone (96a), thiosemicarbazone (96b) and 2,4-dinitrophenyl hydrazone (96c) were all reacted with SOCl2 to yield 9//-l,2,3-thiadiazolo[4,5-a]-4,5,6,7-tetrahydropyrrolizine (97) <83IJC(B)822>. The reaction of varying amounts of benzylamine with 4-bromomethyl-5-benzoyl-1,2,3-thiadiazole (98) gave 5-benzyl-6-phenylpyrrolo[3,4-d]-1,2,3-thiadiazole (83) in low yields <78JHC473>. 

Derivatives of 14-hydroxydihydrocodeinone have been converted into 6a- and 6/ff-amino-compounds by condensation with benzylamine and then reduction and hydrogenolysis of the resulting Schiff-bases,195 and also into their hydrazones.196 Codeine and ethylmorphine have been nitrated and sulphonated at position 1197 and fluoro-compounds of structures (103 R = H), (103 R = OH), (104 R = H), and (104 R = OH) have been prepared from dihydrocodeinone and 14-hydroxy-dihydrocodeinone by treatment with diethylaminosulphur trifluoride.198... 

The hydrazone made from chloral and p-tolylsulfonhydrazide (MeC6H4S02NHN=CHCCl3) and an excess of benzylamine furnished 4-benzylamino-3-benzyltriazole 25°C, 1 hr, 30%) [84EUP(A)103840]. 

Diastereomeric benzylamines are obtained by cinnamylation of imines with alkenylsiladi-oxolane 90. The stereochemical switch requires only a change of the A -substituent. The cognate heterocycle 91 is useful catalyzing addition of ketene silyl ethers to hydrazones. ... 

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