A variety of pentacycloundecane (PCUD) based cage compounds containing nitro groups were synthesized via a simple synthetic method starting with cage diones. Eight PCUDs were used for nitro functionalization. These cage diones were prepared starting with easily accessible starting materials such as 2,3-dimethylhydroquinone, 1,4-dihydroxybenzene, and cyclopentadiene. Here, we have used Diels-Alder (DA) reaction, [2 + 2] photocycloaddition, and Henry reaction as key steps. Transannular cyclization plays an important role to generate a nitro substituted cage heterocycles via base promoted reaction using nitromethane as a reagent. Some of these oxa-cage structures have been further supported by single-crystal X-ray diffraction studies. Energetic performance of the title compounds was evaluated using DFT based calculations. These bis(nitromethyl)octahydro-1H-1,3,4,6(epiethane-[1,1,2,2]tetrayl)-pentaleno[1,6-bc]furan analogues (11 b-18 b) owned the densities in the range of 1.37-1.60 g/cm 3 . All the studied compounds possess high positive enthalpy of formation (33.68-230.48 kJ/mol, except compound with dimethyl groups (16 b, À 11.38 kJ/mol) and very good thermal (T m = 99-147 °C) and kinetic stabilities. Ammonium perchlorate based various propulsion formulations suggests that these compounds could be excellent candidates in the solid rocket propulsion.

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A facile and efficient thiol-free one-pot method for direct synthesis of sulfides and sulfoxides under green conditions without using any metal catalyst is reported.

Herein, we describe a simple synthetic strategy to assemble aza-polyquinane systems containing an indole motif by employing the Fischer indolization and ring-rearrangement metathesis as key steps. The precursor used here is exo-dicyclopentadienone, which is derived from less explored exo-dicyclopentadiene. By using this approach, several aza-polyquinanes that contain indole units and fused medium rings (eight- and nine-membered rings) were synthesized in good yields.

We report a useful synthetic strategy to assemble constrained [3.n] thiacyclophanes using Grignard reaction and Ti(OiPr)4 assisted ring‐closing metathesis (RCM). This method is viable to access para, metapara, and meta isomers of thiacyclophanes. The structures of thiacyclophanes were confirmed unambiguously by single‐crystal X‐ray diffraction studies and compared with computationally optimized structures. It is implied that out of four methods (ab initio and DFT), MP2/6‐31G (d,p) is reasonably a better method for predicting structural parameters for this class of thiacyclophanes.