Synthesis of novel dibenzo-2,6,9-triazabicyclo[3.3.1]nonanes from o-tosylamino- and o-mesylaminobenzaldehydes

Chiral Synthesis of McGeachin-Type Bisaminals

“…The facile trimerization of o -aminobenzaldehyde implies that the condensation between two molecules of o -aminobenzaldehyde with one molecule of primary amines constitutes an efficient method. By using different surrogates of o -aminobenzaldehyde or different acid catalysts, Molina’s, Ukhin’s, Yu and Wang’s, and Sridharan’s groups developed different synthetic routes to McGeachin-type bisaminals with functionalities at the apical nitrogen (Scheme a). In the above-mentioned reports, primary aryl amines (ArNH 2 ) and α-substituted methylamines (R′CH 2 NH 2 ) were used.…”

Synthesis of 6,12-Epiminodibenzo[b,f][1,5]diazocines via an Ytterbium Triflate-Catalyzed, AB2 Three-Component Reaction

“…Although epiminodibenzo­[ b , f ]­[1,5]­diazocines may seem, in principle, easy to access from 2 equiv of 2-aminoarylaldehydes and a primary amine, this approach presents a major limitation associated with the low stability of these aldehydes, where the presence of two highly reactive adjacent functionalities often affords trimerization products rather than the desired compounds, especially in the presence of nucleophiles . For this reason, functionalized 2-aminoarylaldehydes including iminophosphoranes and N -Ts/Ms derivatives have been employed as precursors for the synthesis of epiminodibenzo­[ b , f ]­[1,5]­diazocines combined with primary amines, albeit in low yields. Recently, Yu, Wang, and co-workers reported a simple cascade reaction between 2-aminoarylaldehydes 3 and primary amines in the presence of scandium pentafluorobenzoate .…”

Synthetic strategies and diversification of dibenzo[1,5]diazocines

“…Finally, the nucleophilic attack of amine to carbocation centre gives the corresponding products. 63 To extend the synthetic scope, Ukhin et al 64…”

“…A simple reaction between 2-mesylaminobenzaldehyde and ammonium acetate or primary amines gave the desired 31a-e in 15-34% yields (Scheme 14b). 64 Another synthetic strategy to functionalise McGeachin-type bisaminals was reported by Leganza et al 65 in 2006. They discovered that the addition of ketone 33a to a solution of ketimine 32a in refluxing xylene afforded the desired 34a in good yield (Scheme 15a).…”