Removal of the Chiral Inductor from Phenylglycinol-derived Tricyclic Lactams. Unexpected Generation of Chiral trans-Hydrochromene Lactones
作者:Rosa Griera、Alexandre Pinto、Robert Fabregat、Eric Cots、Joan Bosch、Mercedes Amat
DOI:10.2174/1570178615666171213143657
日期:2018.4.12
In the search for synthetic routes for the preparation of cis- and trans- decahydroquinolin-2-
ones, a procedure for the generation of enantiopure trans-hydrochromene lactones, by treatment of (R)-
phenylglycinol-derived oxazoloquinolone lactams with Na/liq. NH3 followed by acidification, has been
developed.
Hydration of nitriles and transformation of delta-keto nitriles to ene-lactams can be performed efficiently by using RuH2(PPh3)4 catalyst under mild conditions. The effectiveness of the reaction is illustrated by the short-step synthesis of (-)-pumiliotoxin C.
Ruthenium-catalyzed hydration of nitriles and transformation of δ-ketonitriles to ene-lactams: total synthesis of (−)-pumiliotoxin C
1–2 equivalents of water can be performed efficiently by using RuH2(PPh3)4 catalyst to give the corresponding amides. Under the similar reaction conditions, δ-ketonitriles can be converted into the corresponding ene-lactams, which are versatile synthetic intermediates. The efficiency of the reaction is demonstrated by the short-step synthesis of (−)-pumiliotoxin C.