Zur Kenntnis der Pschorrschen Phenanthrensynthese

ATTEMPTS TO FIND NEW ANTIMALARIALS. XVI.1,2 AMINO ALCOHOLS OF THE TYPE —CHOHCH2NR2 DERIVED FROM 3-CHLORO-9-ACETYLPHENANTHRENE

“…The yields of acid V were lower than generally observed in the Pschorr synthesis when the nitro group, instrumental in the ring closure, is located in the aromatic aldehyde. This corroborates the results obtained by Mayer and Baile (3) in the preparation of phenanthrene derivatives from o-nitrophenylacetic acid. The intermediate cinnamic acid derivative III loses water readily, even by recrystallization from ethanol, to form lactam IV which we also prepared by condensing p-chlorobenzaldehyde with oxindole, and which proved to be very resistant to hydrolyzing agents.…”

“…We find now that by employing s-tetrachloroethane as reaction medium, the course of this reaction is considerably altered. 3 We obtained in a 20-25% yield threne, and in about 30% yield a seemingly isomeric ketone which had after purification by crystallization and sublimation, the constant m.p. 103-104°.…”

AN ATTEMPTED SYNTHESIS OF A CYCLOÖCTATETRAENE. CIS-TRANS ISOMERISM OF SUBSTITUTED DI- AND TRI-PHENYLBUTADIENES1

“…This compound was made only by the Perkin condensation of cinnamaldehyde and the sodium salt of o-nitrophenylacetic acid. The sodium salt of o-nitrophenylacetic acid was prepared by the method of Mayer and Baile (19). The sodium salt,4 20.3 g. (0.1 mole), with 13.2 g. (0.1 mole) of cinnamaldehyde and 25 g. of acetic anhydride, was heated ten hours at an oil-bath temperature of 110-120°.…”

“…Trans-ds series. By the condensation of o-nitrobenzaldehyde with sodium 4-phenyl-3-butenoate an acid (XIV) was obtained whose configuration is presumably trans-cis by analogy with other compounds obtained by similar syntheses (19).…”

The Pschorr Synthesis

“…In every case found, acetic anhydride was the acid anhydride used. In some cases a small amount of anhydrous zinc chloride (8,9,35,52,53,54,60) or stannous chloride (26) was added, but the beneficial effect of these "catalysts" is dubious. For instances in which one or the other of these metal chlorides has been used, the average yield was approximately 10 per cent lower than the aver- age yield for this step of the Pschorr synthesis.…”