0000000000812748
AUTHOR
Jan-gernot Deichmann
A one-pot cascade to protoberberine alkaloids via Stevens rearrangement of nitrile-stabilized ammonium ylides.
A facile one-pot synthesis of protoberberines from readily accessible 1,2,3,4-tetrahydroisoquinoline-1-carbonitriles and 1,2-bis(bromomethyl)arenes is described. The reaction cascade comprises four consecutive transformations, all of which can be effected under a single set of conditions. Ten protoberberines, including the alkaloids pseudopalmatine and pseudoepiberberine, were prepared in yields up to 86% according to this strategy. No chromatographic purification of the products is required, and the route is devoid of any protecting group manipulations.
ChemInform Abstract: A One-Pot Cascade to Protoberberine Alkaloids via Stevens Rearrangement of Nitrile-Stabilized Ammonium Ylides.
This method gives access to quaternary protoberberines including naturally occurring pseudopalmatine (IIIf) and pseudoepiberberine (IIIg).