Aniline Fentanyl

Methenolone acetate A ndro tardy 1-0 estradiol Estradiol valerate Aniline Fentanyl Salicylanilide Anisoyl chloride Benzobromarone... 

Reduction of Schiff base (XXXI) formed between l-phenethyl-4-piperidone and aniline, and acylation of the resultant dibase gives the highly potent analgesic [112] fentanyl(Sublimaze,XXXIla). In mice (tail-clip method), fentanyl... 

Fentanyl and its analogs are made from TV-substituted-4-piperidones [i.e., from the same intermediates of the reversed esters of pethidine (p. 266)]. These ketones condense with aniline under the influence of catalysts such as toluene-p-sulfonic acid(2) and zinc chloride(18) to give Schiff bases, which are reduced to diamines 4 by NaBH4 or LAH. Recently, the direct conversion of 4-piperidones to 4-anilino derivatives 4 has been achieved by reductive amination with aniline and sodium cyanoborohydride (NaBH3CN).(19) The diamines are acylated with propionic anhydride. 

The 4-substituted fentanyls 13-15 were prepared by manipulations of the cyano function of intermediates of type 16, themselves made by treating a 4-piperidone with aniline HC1 and KCN.(42)... 

N-(4-Piperidyl) propioanilide is prepared by the condensation of propionyl chloride with N-(4-piperidyl)-aniline. The resulting product is further condensed with phenethyl chloride to obtain the corresponding fentanyl base which on reaction with an equimolar portion of citric acid gives rise to the (1 1) citrate. 

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