The methiodides (XXIV-i and -ii) of the N-methylalkylpyrrolidine compounds were each submitted to the Hofmann degradation with silver oxide and the methine (XXV-i), b.p16 84°, [α]D15: +14.5α, and (XXV-ii), b.p21 85-86°, were respectively obtained. Ozonic oxidation of (XXV-i) and (XXV-ii) afforded, from (XXV-i) the dimethylamino ketone compound (XXVI-i), b.p19 105-106°, [α]D16: +30°, which formed semicarbazone of m.p. 115-116°, [α]D15: -27.5° (MeOH), [α]D20: -38° (AcOEt); picrate of m.p. 106-108°, [α]D19: +17° (MeOH), and from (XXV-i), (XXVI-ii), b.p19 100-104°, forming a semicarbazone of m.p. 109-110°, [α]D20: 0° (MeOH or AcOEt), picrate of m.p. 114-115°, [α]D18: 0° (MeOH). Since the foregoing two semicarbazones gave identical infrared absorption curves in carbon tetrachloride, (XXVI-ii) must be the racemate of (XXVI-i). Secondstage Hofmann degradation was then carried out on the syrupy methiodide of (XXV-i) with silver oxide or on the methiodide (XXIX-i), m.p. 207°, C13H30NI, of the dihydromethine compound (XXVIII-i), b.p16 85-86°, obtained by the catalytic reduction of (XXIV-i), with silver oxide or conc. sodium hydroxide solution, or both but the anticipated objective compound was not obtained, recovering (XXVI-i) or (XXVIII-i). Such results only endorsed the previous conclusion and failed to give conclusive evidence as to which of the proposed formulae, given in the preceding paper, is correct.
