Azo Bridges from Azines, XXIII. 1,5-Laticyclic Conjugation Between Parallel Azo ando-Phenylene Bridges. Structure Dependence of [6 + 2] Photocycloadditions
作者:Karin Beck、Uwe Brand、Siefried Hünig、Hans-Dieter Martin、Bernhard Mayer、Karl Peters、Hans Georg von Schnering
DOI:10.1002/jlac.199619961125
日期:1996.11
rigid parallelo o-phenylene and azobridges are connected to five- and/or six-membered carbocyclic moities. The o-phenylene bridge was introduced by two routes: (A) starting from precursors already containing that bridge (24, 29) and assembling the azobridge in consecutive steps ( 3a, 3b, 5c, 5d, 5e, 5f, 5g); (B) starting from the systems with parallel CC/NN bridges (9a, 11a, 13a, 42) and completing
合成了四个系统1、3、5和7的示例,其中刚性平行六烷基邻苯撑和偶氮桥连接到五元和/或六元碳环部分。所述Ô亚苯基桥通过两种途径引入:(A)从已经包含桥(前体开始24,29)及装配在连续的步骤的偶氮桥(3A,3B,5C,5D,5E,5F,5G); (B)从具有平行CC / NN桥(9a,11a,13a,42)的系统开始,并通过四氯噻吩二氧化物完成二氢邻苯撑环。偶氮桥的正离子氢转移增强了中间体二氢芳烃的脱氢作用ø亚苯基衍生物(22,3CH 2,25)。多米诺氢转移44 45 5h证明了这一机理。通过路线B,获得系统1a,1b,3c,3d,5a,5b,5h和43。与此形成鲜明对比的是平滑的[2 + 2]的系统光环9,11,13,和15(CC / NN桥),[6 + 2]光环只发生与系统1和(5 ç / 5 Ñ)和3(6 C / 5 N),但不适用于系统5(5 C / 6 N)和7(6 C / 6
Azo bridges from azines. XV. Oxygenation of Unsaturated Cyclic Azo Compounds with peracids
作者:Siegfried H�nig、Michael Schmitt
DOI:10.1002/prac.19963380113
日期:——
Azo bridges in compounds 3, 6, 11, 16, 20 and 22 are chemospecifically oxidized with MCPBA to the corresponding azoxy derivatives 4, 7, 12, 17, 21, and 23 in the presence of one or two (20, 22) double bonds even if these are located in a close parallel position to the azo bridge (6, 11, 20, 22). The order of reactivity of different olefinic moieties towards MCPBA was found to be bicycloheptene > bicyclooctene, cyclopentene. Thus, epoxy/azoxides 5, 8, 13, 14, and 19 as well as bisepoxy/azoxides 10 and 15 were obtained. If both the azo and the olefinic bridge are part of a bicycloheptane system (24) the azo group can be no longer oxidized chemospecifically (25 + 26).
HUENIG, S.;PROKSCHY, F., CHEM. BER., 1984, 117, N 2, 534-553