160857-66-9

Upstream product

• 129913-14-0 (3,4-dimethoxyphenyl)ketene 
• 160857-70-5 (3-benzyloxy-6-bromo-4-methoxyphenethylimino)triphenylphosphorane 
• 25349-38-6 4-[(E)-(3,4-dimethoxyphenyl)methylidene]-2-phenyl-1,3-oxazol-5(4H)-one 
• 93-40-3 (3,4-Dimethoxyphenyl)acetic acid 
• 141035-23-6 5-Benzyloxy-2-brom-4-methoxy-phenaethylamin 
• 55323-56-3 2-(5-benzyloxy-2-bromo-4-methoxyphenyl)ethanol 
• 120-14-9 3,4-dimethoxy-benzaldehyde 
• 697803-44-4 1-Benzyloxy-4-bromo-2-methoxy-5-vinyl-benzene 
• 697803-43-3 (E)-3-benzyloxy-6-bromo-4-methoxy-β-chlorostyrene 
• 918896-58-9 1-benzyloxy-4-bromo-2-methoxy-5-[2-nitro-(E)-1-ethenyl]benzene 

Downstream Products

• 158837-99-1 8-Benzyloxy-1-(3,4-dimethoxy-benzyl)-7-methoxy-3,4-dihydro-isoquinoline 
• 697803-46-6 1-(3,4-Dimethoxy-benzyl)-7-methoxy-3,4-dihydro-isoquinolin-8-ol 
• 479-39-0 (+)-cularine 

Relevant academic research and scientific papers

AN EASY ENTRY TO ISOQUINOLINE ALKALOIDS BY AZA-WITTIG ELECTROCYCLIC RING-CLOSURE

The reaction of phenethyliminophosphorane with arylketenes gave 1-benzyl-3,4-dihydroisoquinolines in good yields.An aza-Wittig type reaction of vinyliminophosphorane with p-toluenesulfonylisocyanate furnished 1-aminoisoquinoline 6 in high yield. - Key wor

Diastereoselective Synthesis of Cularine Alkaloids via Enium Ions and an Easy Entry to Isoquinolines by Aza-Wittig Electrocyclic Ring Closure

In preliminary communications, we reported the diastereoselective synthesis of cularine and sarcocapnine via the intramolecular ring closure of nitrenium and oxenium ions, a new highly diastereoselective reductive methylation with (+)-8-phenylmenthyl chloroacetate followed by reduction with sodium borohydride, and a facile entry to the isoquinoline precursors by aza-Wittig electrocyclic ring closure. We now report the full details of the syntheses of (+)-O-demethylcularine, (+)-cularine, (+)-sarcocapnidine, (+)-sarcocapnine, and (+)-crassifoline and describe different methods of synthesis of their precursors.