Degradation with hydrazine

Phenylethylamine has been made by a number of reactions, many of which are unsuitable for preparative purposes. Only the most important methods, from a preparative point of view, are given here. The present method is adapted from that of Adkins,1 which in turn was based upon those of Mignonac,2 von Braun and coworkers,3 and Mailhe.4 Benzyl cyanide has been converted to the amine by catalytic reduction with palladium on charcoal,5 with palladium on barium sulfate,6 and with Adams catalyst 7 by chemical reduction with sodium and alcohol,8 and with zinc dust and mineral acids.9 Hydrocinnamic acid has been converted to the azide and thence by the Curtius rearrangement to /3-phenyl-ethylamine 10 also the Hofmann degradation of hydrocinnamide has been used successfully.11 /3-Nitrostyrene,12 phenylthioaceta-mide,13 and the benzoyl derivative of mandelonitrile 14 all yield /3-phenylethylamine upon reduction. The amine has also been prepared by cleavage of N- (/3-phenylethyl) -phthalimide 15 with hydrazine by the Delepine synthesis from /3-phenylethyl iodide and hexamethylenetetramine 16 by the hydrolysis of the corre-... 

Accurate determination of hydrazine and dimethylhydrazines in environmental samples is also complicated by the susceptibility of these chemicals to oxidization. Air samples must be analyzed immediately after collection (Cook et al. 1979). Degradation of hydrazine in aqueous samples can be prevented by acidification with sulfuric acid (WHO 1987). 

The degradation of alkaloids of ergot with hydrazine to lysergic acid hydrazide is, especially with respect to the obtained 5neld, much... 

The structure of ophiobolin A (5.137) was established by chemical degradation and by X-ray crystallography of a bromo derivative. The spectroscopic characteristics of ophiobolin A led to the identification of the oxygen functions and the double bonds. The relationship between the aldehyde and the cyclo-pentanone was revealed by the formation of a y-lactone on reduction and partial re-oxidation. A cyclic pyridazine was formed with hydrazine. Tetra-hydro-ophiobolin A formed an unusual cyclic peroxide involving these two groups. Vigorous oxidation of tetrahydro-ophiobolin A afforded a heptanoic acid lactone, which revealed the structure of the side-chain. 

Vomifoliol (97) isolated from Rauwolfia vomitoria appears to be a degradation product of abscisic acid and possibly a precursor of theaspirone. Damas-cenone, a minor component of Bulgarian rose oil, was shown to be the cross-conjugated isomer (98) of dehydroionone. A tetrahydro-damascenone was prepared by treating a-ionone-7,8-oxide with hydrazine. ... 

The chemical reactivity of all of the compounds of this series is governed by the powerful, electron-withdrawing influence of the sulfonyl groups this renders the acyclic, saturated members liable to eliminations, and the acyclic, unsaturated members susceptible to attack at C-2 by nucleophiles, and makes both the cyclic and the acyclic members unstable in basic solutions. This last feature provides the main source of interest in these compounds, all of which are degraded by aqueous ammonia to diethyl-sulfonylmethane and the aldose derived from the parent sugar by loss of C-1. Treatment with hydrazine in methanol, followed by cleavage of the derived hydrazone, offers a satisfactory means for degrading the acetylated sulfone (148) to n-arabinose (yield, 73%). ... 

Commercial products are additionally stabilized against thermal degradation with polyamides, hydrazine, urea, or thiourea. All of these additives react with formaldehyde or its reaction products, such as formic acid. Secondary and tertiary amines are also added to improve the resistance to oxidation, and carbon black or special UV stabilizers are used to increase light stability. 

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