New heterocyclic systems—I 5,6-dihydro-7H, 12H-dibenz[c,f]azocine

Conformational properties of cis,cis-1,4-cyclooctadiene. Dynamic nuclear magnetic resonance spectroscopy and iterative strain-energy calculations

“…The twist-boat (TB) or flexible4 family of conformations of 1,4-cyclooctadiene was obtained by "driving"150'21•22 the C(6)-C (7) or C(7)-C(8) torsional angle of the boat-chair conformation by steps of 10 to 15°to give a smooth conformational change, as shown in Figure 4. The twist-boat family of conformations includes the axial-symmetrical twist-boat (TB, Ci) itself and a distorted twist-boat (DTB) which lacks symmetry (there are actually two distorted twist-boats when the molecule is labeled).…”

Structural studies of dibenz[c,f]azocines. I. N-Methyl-5,6-dihydro-7H,12H-dibenz[c,f]azocine

“…Several N-derivatives of 5, 6-dihydro-7H,12H-dibenz-[c,f] logical screening by Casadio, Pala, Crescenzi, MarazziUberti, Coppi & Turba (1968), and by Pala, Mantegani & Zunga (1970). The conformational properties in solution of the N-methyl derivative have been determined by Renaud, Layton & Fraser (1973) from a study of its n.m.r, spectrum.…”

Ring Expansion of 1,2,3,4-Tetrahydroisoquinolines to Dibenzo[c,f]azonines. An Unexpected [1,4]-Sigmatropic Rearrangement of Nitrile-Stabilized Ammonium Ylides

“…However, synthetic efforts toward the preparation of dibenzo[ c , f ]azonines are rather limited. The first approach to this compound class was reported by Zugna and co-workers, who treated 2,2′-bis­bromo­methyl­di­phenyl­methane with sodium cyana­mide or benzyl­amine to give the ring-closed substitution products . Manning and Houlihan patented the synthesis of dibenzo[ c , f ]azonines from iso­indolo[1,2- a ]iso­quino­linum salts by reduction with sodium in liquid ammonia to cleave the central bond between C-12b and nitrogen. , A Sommelet–Hauser rearrangement of 1-phenyl­tetra­hydro­iso­quino­linium methylides to dibenzo[ c , f ]azonines was reported by Sato et al The latest report on this class of hetero­cycles is a patent by Dreux and co-workers describing a sequential reduction, hydrolysis, and intra­molecular cyclo­condensation of ethyl-3-(3-methoxy­benzyl­amino)-4-(3,4-di­methoxy­phenyl)-2-butenoate…”