3-Methyl-1,2,3,4,5,6,1′,2′,3′,4′-decahydrospiro[benz[f]isoquinoline-1,2′-naphthalen]-1′-one

Abstract

The title compound, C23H23NO, is the product of a tandem transformation of the double Mannich base bis­(1-oxo-1,2,3,4-tertrahydro-2-naphtho­ylmeth­yl)amine hydro­chloride in HBr solution upon heating. The tetra­hydro­pyridine ring has a non-symmetrical half-chair conformation, whereas the cyclo­hexa­diene and cyclo­hexene rings adopt non-symmetrical half-boat conformations. The dihedral angle between the planes of the terminal benzene rings is 62.85 (6)°. The N atom has a trigonal–pyramidal geometry [sum of the bond angles = 332.4 (3)°]. In the crystal, mol­ecules form [001] chains via weak non-classical C—H⋯N hydrogen bonds. The chains are stacked along the b axis.

Crystal structure and features of 3′,8-dibenzylidene-4a,5,6,7,8,8a-hexahydro-2′H-spiro[chromene-2,1′-cyclohexan]-2′-one

“…The structure and configuration of the molecule is complex and includes a spiro node and arylmethylidene moieties. A similar spiro ring based on the Mannich ketone was described earlier (Siaka et al, 2012). The tetrahydropyridine ring is in an unsymmetrical half-chair conformation, while the cyclohexadiene and cyclohexene rings display semi-boat conformations.…”

Uncommon expansion of piperidine ring into hydroazocine ring in reactions of some piperidine β-acyl derivatives with acetylenecarboxylic acids esters

“…This zwitter ion then suffers an intramolecular decyclization of retroaldol type which may be accompanied with the tautomeric enolization and the formation of a linear adduct C (Scheme 2). Similar 1,3-zwitter ions containing in their structure an allylamine fragment may undergo an intramolecular [1,3]-sigmatropic rearrangement (through a fourmembered transition state [14]) with the cleavage of the N-С sp3 bond and the insertion of the residue of maleic acid ester. The possibility of such processes was mentioned in [9,10].…”

“…This cascade reaction proceeds similarly to α-tetralone condensation through Mannich base A [2][3][4] that further undergoes cyclization into γ-piperidol derivative due to an intramolecular condensation of aldol type [5,6] (Scheme 1).…”

rac-(1S*,4aS*,8aS*)-4a-Hydroxy-2-methylperhydrospiro[isoquinoline-4,1′-cyclohexan]-2′-one

“…These mixtures contain only trace quantities of the expected piperidols (identified by LC-MS method). It is interesing to note that heating of the analogous double Mannich base prepared from α-tetralone (Soldatenkov et al, 2009;Soldatova et al, 2010;Siaka et al, 2012) in HBr solution gives the expectable product of the cyclization, but in the dehydrated form. Its structure comprising the spiro-fused hexahydrobenzo[f]isoquinoline and tetrahydronaphthalenone systems was unambiguously established by X-ray diffraction study (Siaka et al, 2012).…”

“…For general background to the synthesis, chemical properties and applications in medicine of the title compound, see: Plati & Wenner (1949); Ellefson et al (1978); Soldatenkov et al (2009). For related compounds, see: Plati & Wenner (1950); Soldatenkov et al (2008); Soldatova et al (2010); Siaka et al (2012).…”