Syntheses of Pentacyclo(5.4.0.0(2,6).0(3,10).O(5,9))undecane-4,8,11-trione, Pentacyclo(6.3.0.0(2,6).0(3,10).0(5,9))undecane-4,7,11-trione (D3-Trishomocubanetrione), and 4,4,7,7,11,11-Hexanitro(6.3.0.0(2,6).0(3,10).0(5,9)undecane (

摘要

The title compounds (1, 2a and 2b, respectively) have been synthesized from 4,4-dimethoxypentacyclo(5.4.0.02,6.03,10.05,9)undecane-exo,exo-8,11- diol (4). Thus, hydrolysis of the ketal functionality in 4 followed by oxidation of the resulting ketodiol afforded 1 in essentially quantitative yield. When 4 was heated with acetic acid in the presence of concentrated sulfuric acid, a mixture of cage ketodiacetates 6 and 7 was produced. Compound 2a was synthesized in several steps from this mixture by using the route shown in Scheme I. This synthesis could be shortened considerably when propionic acid was substituted for acetic acid in the acid-promoted rearrangement of 4. An improved synthesis of 2a based on this latter approach is shown in Scheme II. Compound 2a was then converted into the corresponding tris(oxime) from which the corresponding D3-hexanitrotrishomcubane (2b) could be synthesized by using an established literature procedure.