Highly Diastereoselective Synthesis of New trans-Fused Octahydro­acridines via Intramolecular Cationic Imino Diels–Alder Reaction of N-Protected Anilines and Citronellal or Citronella Essential Oil

Abstract

Supporting information Contents: 1-General experimental information, (Page S1) 2-Extraction and characterization of the essential oil of citronella (Cymbopogon nardus), (Page S9) 3-1 H NMR and 13 C NMR spectra of trans N-benzyl octahydroacridines 16-21, (Page S10) 4-1 H NMR and 13 C NMR spectra of trans NH-octahydroacridines 22-24, (Page S23) 5-Single crystal X-Ray diffraction data for trans N-benzyl octahydroacridine 16, (Page S28)

The Intramolecular Povarov Tool in the Construction of Fused Nitrogen-Containing Heterocycles

“…A one-pot diastereoselective synthesis of new N -substituted octahydroacridines was successfully achieved by Kouznetsov et al. [ 113 , 114 ] via BiCl 3 -catalyzed intramolecular cationic imino-Diels–Alder reaction. The intermediate iminium ions were prepared in situ through condensation of N -protected anilines 342 and (±)-citronellal 38 under mild reaction conditions (Scheme 93 ).…”

Essential Oils and Eutectic Solvents in the Povarov Reaction for the Synthesis of Tetrahydroquinolines: A Lesson of Cycloadditions, Stereochemistry, and Green Chemistry

“…In these synthesis, as well as for the obtention of benzofuran and dioxane, the propenyl group present in eugenol and trans -anethole is the key fragment while the hydroxy group and the aromatic ring in carvacrol and eugenol are fundamental for the construction of the chromene ring . Finally, the epoxide ring is formed on a double bond of geraniol and the carbonyl group together with the olefinic fragment in citronellal allows the assembly of the acridine core. − …”