75767-96-3

Upstream product

• 63375-81-5 2-(2-bromo-4,5-dimethoxyphenylphenyl)ethan-1-amine 
• 100-52-7 benzaldehyde 
• 120-20-7 2-(3,4-dimethoxyphenyl)-ethylamine 

Downstream Products

• 4118-36-9 6,7-dimethoxy-1-phenyl-1,2,3,4-tetrahydroisoquinoline 
• 190510-99-7 1-(2-bromo-4,5-dimethoxyphenethyl)-2-phenyl-2,3-dihydropyridin-4(1H)-one 
• 190511-13-8 N-[2-(2-bromo-4,5-dimethoxyphenyl)ethyl]-2,3-didehydro-3-ethyl-4-oxo-6-phenylpiperidine 
• 74421-96-8 N-benzyl-2-bromo-4,5-dimethoxyphenethylamine 
• 152913-91-2 N-<β-(2-bromo-4,5-dimethoxyphenyl)ethyl>-N-formyl-1-aminoindene 
• 162330-95-2 β-(2-bromo-4,5-dimethoxyphenyl)-N-methylethylamine 

Relevant academic research and scientific papers

Stereoselective synthesis of benzoquinolizidines and related homologues via intramolecular addition to dihydropyridones

An efficient method for the synthesis of benzoquinolizidine and benzoindolizidine alkaloid scaffolds is described. The synthetic strategy is based on the lithium-halogen exchange-initiated intramolecular conjugate addition of aryllithiums to 2,3-dihydro-4-pyridones. A similar cyclization was also carried out under free radical conditions providing the expected cyclic compounds, although with significantly lower yields. The effects of chain length and acceptor substitution pattern on the feasibility of ring construction were studied.

Phosphane-free Pd0-catalyzed cycloamination and carbonylation with Pd(OAc)2 and Cu(OAc)2 in the presence of K 2CO3: Preparation of benzocyclic amines and benzolactams

Phosphane-free Pd0-catalyzed intramolecular aromatic amination was studied. o-Halophenethylamines and 3-(o-halophenyl)propylamines were found to be transformed into indolines and quinolines in a catalytic system based on Pd(OAc)2 and Cu(OAc)2 in the presence of K 2CO3. Application of the method to substrates containing isoquinoline rings- the 1-(o-bromobenzyl)-3,4-dihydroisoquinolines 6, the 1-(o-bromobenzyl)-1,2,3,4-tetrahydroisoquinolines 7, and the 1-(o-bromophenethyl)isoquinolines 9- provided the indolo[2,1-a]isoquinoline and dibenzo[a,f]quinolizine ring systems 8 and 10. Extension of the method to β-carbolines (compounds 11, 12, and 17) produced the benz[f]indolo[2,3-a] indolizine-13-ones 15 and the benz[f]indolo[2,3-a]quinolizine 18. The benzo[f]pyrido[3,4-a]indolizine and indolo[f]pyrido[3,4-a]indolizin-12-one ring systems 27 and 31 were built in a similar manner. It was also found that under an atmosphere of CO the same catalytic system produced the corresponding benzolactams, the isoquino[2,1-a][2,7]naphthyridine 34 and the indolo[2,3-a]pyrido[g]quinolizin-8-one 36 [(±)-dihydronauclefine] in good yields. Copyright

Three-Step Access to the Tricyclic Benzo[a]quinolizine Ring System

Access to the tricyclic benzo[a]quinolizine ring system, which forms the characteristic framework of alkaloids of the berberine and emetine type, is readily obtained by a three-step reaction sequence. This sequence includes the formation of a Schiff base, derived from a 2-bromo-substituted phenylethylamine, and its tandem Mannich/conjugate addition reaction with an electron-rich silyloxy diene forming an intermediate enaminone, which subsequently undergoes a Heck-type cyclization. Highest yields of the tandem Mannich/conjugate addition for aromatic Schiff bases and formaldehyde imines are observed in the presence of ZnCl2 in THF, whereas aromatic imines give the best results in the presence of EtAlCl2 in CH2Cl2. The best results for the Heck-type cyclizations are obtained either under heterogeneous conditions in the presence of K2CO3/NEt4Cl at 120°C in DMF or in refluxing toluene or under homogeneous conditions at 100°C in DMF in the presence of NEt-(i-Pr)2. Depending on the substitution pattern of the diene and the steric demand of the base employed in the Heck cyclization, benzo[a]quinolizines carrying a double bond in the 11b,1- or 3,4-position or in an exocyclic position are obtained with fair to good results. A mechanistic rationale for this behavior is proposed. If chiral amines, e.g., derived from an amino acid ester, are employed in the three-step reaction sequence, chiral tricyclic benzo[a]quinolizines become accessible in a straightforward manner.

A Photochemical Synthesis of Benzindenoazepines

A novel synthesis of benzindenoazepine (10) has been achieved by photochemical cyclization of the bromo enaminone (8).On the other hand, irradiation of enolates and enamides failed to give the cyclized azepines.

Schiff Bases as External and Internal Electrophiles in Reactions of Functionalized Organolithium Reagents. A New Route to Isoindoline Derivatives and 1,2,3,4-Tetrahydroisoquinolines

Reaction of Schiff bases with certain functionalized organolithium reagents is useful in the synthesis of 1,2-diarylisoindolines and 2,3-diarylphthalimidines.Schiff bases derived from 2-(2-bromophenyl)ethylamines on halogen-metal exchange with butyllithium undergo a Parham-type cyclization to yield 1-aryl-1,2,3,4-tetrahydroisoquinolines.