Phenylhydrazine 9-Phenylhydroxylamine

The condensation of nitrosobenzene with phenylhydroxylamine which is described below is an example of this similarity. Hydroxyl-amine and phenylhydrazine also react with nitrosobenzene, but the details of these reactions cannot be given here. 

A variant on the traditional method is to use a phenylhydroxylamine instead of a phenylhydrazine. For example, A-(benzyloxycarbonyl)-phenylhydroxylamine can be reacted with methyl propynoate to give an adduct that spontaneously undergoes a [3,3]-sigmatropic shift and eventually yields l-(benzyloxycarbonyl)-3-(methoxycarbonyl)indole (Scheme 7.15). 

NTI (82) and its TV -mcthyl analogue (114) were prepared from naltrexone through a Fischer indole synthesis by treatment with phenylhydrazine and methylphenylhydrazine respectively [170, 187]. NTB (115) was synthesized by reaction of naltrexone with O-phenylhydroxylamine [188],... 

PHENYL-4-(3, 4 -DmETn0XYBENZAL)-OXAZOLONE, 13, 8 Phenylhydrazine, 10, 113 /3-Phenylhydroxylamine, 10, 113 Phenylpropiolic acid, 12, 60 Phenyl propionate, 13, 90, 91 Phenyl thienyl ketone, 12, 62... 

Replacing phenylhydrazine by an O-arylhydroxylamine derivative (p. 511) leads to benzofurans phenylhydroxylamine hydrochloride and a ketone may be similarly cyclized in acetic acid-sulphuric acid or in 98% sulphuric acid. 

Transformations which are mechanistically analogous to the Fischer, and also produce indoles, use phenylhydroxylamines instead of phenylhydrazines, as shown below. " ... 

Indolomorphinans can be prepared from their 6-ketomorphinan precursors via Fischer indole synthesis with phenylhydrazine hydrochloride in glacial acetic acid [43, 49, 50], while benzofuromorphinans can be synthesized from the corresponding 6-ketomorphinans using O-phenylhydroxylamine hydrochloride and methanesulfonic acid in MeOH (Scheme 8) [43]. 

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