6533b831fe1ef96bd1299990
RESEARCH PRODUCT
Enantioselective Synthesis of Tetrahydroprotoberberines and Bisbenzylisoquinoline Alkaloids from a Deprotonated α-Aminonitrile
Nancy BlankTill Opatzsubject
Molecular StructureChemistryBerberine AlkaloidsOrganic ChemistryEnantioselective synthesisStereoisomerismStereoisomerismAlkylationTransfer hydrogenationBenzylisoquinolinesAlkaloidsDeprotonationNitrilesMoleculeOrganic chemistryBenzylisoquinolinesBerberine Alkaloidsdescription
Under controlled conditions, 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-1-carbonitrile can be quantitatively deprotonated in the α-position. Its alkylation directly furnishes 3,4-dihydroisoquinolines which can serve as starting materials for the preparation of various alkaloids. Here, the preparation of the benzylisoquinolines (+)-laudanidine, (+)-armepavine, and (+)-laudanosine as well as the tetrahydroprotoberberines (-)-corytenchine and (-)-tetrahydropseudoepiberberine using Noyori's asymmetric transfer hydrogenation are described. The dimeric alkaloids (+)-O-methylthalibrine and (+)-tetramethylmagnolamine were obtained from nonracemic precursors in Ullmann diaryl ether syntheses.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-10-26 | The Journal of Organic Chemistry |