Synthesis of Nitro Derivatives of Peristylane Having High-Density Characteristic

Article abstract of DOI:10.1021/jo00256a012

Reduction of the dioxime of <4>peristylane-2,6-dione (8) with sodium cyanoborohydride delivered the bis(hydroxylamine) 9, which was directly condensed with N-benzylidenebenzenesulfonamide and benzaldehyde to give the bis(nitrone) 10.Ozonolysis of 10 gave rise to endo,endo-2,6-dinitro<4>peristylane (6).In a separate sequence, 8 was oxidized with 100percent nitric acid in the presence of ammonium nitrate.The resulting dinitro ketone 11 was oximated and then oxidatively brominated.When sodium borohydride reduction of 14 was uncovered to proceed with transannular CC bond formation, the dinitro oxime 12 was instead oxidized as above.The reaction afforded the targeted 2,2,6,6-tetranitro<4>peristylane (7).Density measurements performed on 6, 7, 11, and 13 indicate that the presence of one geminal pair of nitro groups increases crystal packing efficiency steeply.However, the presence of a second pair of nitro groups transannular to the first has little more impact than positioning of a ketone carbonyl or lactone bridge at that site.