7,8,9-Trimethoxy-4a,10b-trans- and -4a,10b-cis-1,2,3,4,4a,5,6,10b-octahydrophenanthridines. Configurational and conformational changes in epimerization of N-substituted derivatives

Abstract

Several weeks at room temperature were required for the reequilibration.Hexafluoroacetone Dimethylhydrazone (4).-2,2,2-Trifluoro-1 -(trifluoromethyl)ethylidenimine (11 ml) was bubbled into a chilled solution of 6.0 g of N,A-dimethylhydrazine in 25 ml of ether. After the addition was complete, the solution was warmed to room temperature and poured onto 30 g of phosphorus pentoxide.Distillation gave only a trace of the desired hydrazone. The product was purified by gas chromatography on a 6 ft X 0.25 in. column of 20% silicone #200 on 60/80 Chromo "W."At 50°a nd 10 cc/min the retention time was 50 min; pmr (CC14) 6 3.24 (q, J = 1.2, q,J = 2.4 Hz).Anal. Caled for CóHeF6N2: mol wt, 208.0434. Found: mol wt, 208.0429 (high-resolution mass spectrum).l-[l-(Trifluoromethyl)ethylidenehydrazono]-l-(trifluoromethyl)ethane.-To a stirred solution of 25 g of trifluoroacetone in 200 ml of ether at -30°was added dropwise 25 g of anhydrous hydrazine. An extremely exothermic reaction occurred. The solution was allowed to warm to room temperature and phosphorus pentoxide was added until further addition produced no change. The solution was distilled through a spinning-band column, giving 10 g of product as a pale yellow liquid: bp 58-62°( 180 mm); 18F nmr (CC14) -73.48 (s); pmr 1.5 (s);

The Proton Complex of a Diaza-macropentacycle: Structure, Slow Formation, and Chirality Induction by Ion Pairing with the Optically Active 1,1′-Binaphthyl-2,2′-diyl Phosphate Anion

“…As for (α i ,α′ i )/N H + , the stereochemical relationships between vicinal methylenic protons are the same in solution and in the crystal, as shown qualitatively in Table S5 (Supporting Information). Therefore [ 1 ·H] + behaves as a conformationally fixed tertiary amine, where dihedral angles are well-defined, similarly to small cycles or fused cyclic structures. − ROESY correlations involving aromatic and aliphatic protons (3 i /α i and 3 i /α′ i ; 5 i /β i ; b i /α′ o , b i /β i , b i /γ′ i and b i /δ; 3 o /α′ o ; 5 o /β′ o and 5 o /γ′ o ; b o /β′ o , and b o /γ o ) are also informative. The four latter are consistent with the equatorial orientation of the exo Ts, while b i /β i , b i /γ′ i , and b i /δ agree with the axial orientation of the endo Ts.…”

Homobenzylic and homoallylic spin-spin coupling interactions in some octahydro- and hexahydrophenanthridines

“…In a previous communication1 we reported that the signals assigned to H-6' in the NMR spectra of 1 showed splittings of ca. 1.5 Hz in addition to those expected from geminal coupling between H-6 and H-6'.…”