196-64-5Relevant academic research and scientific papers
Functionalized Enantiomerically Pure -, -, -, and Triblattanes
Mueller-Boetticher, Hermann,Fessner, Wolf-Dieter,Melder, Johann-Peter,Prinzbach, Horst,Gries, Stefan,Irngartinger, Hermann
, p. 2275 - 2298 (2007/10/02)
The methylene (2, 7, 10) and spirocyclopropane derivatives (8, 11, 12) are made accessible from rac-trishomocubane(mono-, di-, tri-)ones and optically pure unsaturated and benzoannulated - (19, 48), - (30, 53), and D3-symmetrical triblattanes (3, 4) from the enantiomers of these ketones by expeditious (one pot) ring enlargement and olefination procedures.In the case of the central trienes (+)-3/(-)-3, novel members of the (CH)14 family, optical resolution is advantageously postponed to the stage of the intermediate triones (35, 41) and effected via their (R,R)-2,3-butanediol acetals.In the α-diketone series only the dione (70) is sufficiently stable to allow isolation; tetrone 73 and hexone 5 are indirectly identified as quinoxalines 74 and 76; respectively.Tribenzotriblattane (-)-4 is established as the M-helical enantiomer by X-ray crystallography.Generally the thermal stabilization pathway of unsaturated and benzoannulated triblattanes is a cycloreversion with the primary cycloreversion products 2,7>tetradeca-3,5,9,11,13-pentane (78) from rac-3> being unstable under the drastic reaction conditions required.The stereochemical course of the perepoxidation of rac-3 is investigated. - Key Words: Trishomocubanes/ Spirocyclopropanes/ -, -, -, Triblattanes
