Syntheses of cisoid and transoid analogs of phenethylamine

N-(Iodopropenyl)-octahydrobenzo[f]- and -[g]quinolines: Synthesis and Adrenergic and Dopaminergic Activity Studies

“…In expanding the aminotetralin system of 3 to the tricyclic structures of 4 and 5 , an additional rigidity factor was introduced in the target molecules: The possibility of the cis or trans fusion of the B/C rings had to be considered, and given the higher activity of the latter as reported in the literature, an improved synthetic path was followed for the synthesis of octahydrobenzo[ f ]quinolines. Considering a number of setbacks of various procedures reported to date, − a new synthetic pathway was designed for the preparation of the [ g ] analogues.…”

“…Reduction of the carbonyl group of 16a , b with lithium aluminum hydride followed by sodium borohydride/acetic acid treatment yielded the trans compounds 18a , b as the major products. The verification of the trans fusion of the B/C rings was established by the NMR spectra of the N -benzyl derivatives. − ,, At the trans-fused rings the N -benzyl methylene protons appear as a pair of doublets which have a large chemical shift difference, whereas at the cis compounds these benzyl protons appear as a singlet. The IR spectra of 18a , b again exhibited the typical for trans fusion “Bohlman bands”.…”

“…The verification of the trans fusion of the B/C rings was established by the NMR spectra of the N-benzyl derivatives. [9][10][11][12]16,17 At the trans-fused rings the N-benzyl methylene protons appear as a pair of doublets which have a large chemical shift difference, whereas at the cis compounds these benzyl protons appear as a singlet. The IR spectra of 18a,b again exhibited the typical for trans fusion "Bohlman bands".…”