Highly Chemoselective Pd−C Catalytic Hydrodechlorination Leading to the Highly Efficient N-Debenzylation of Benzylamines
摘要:
In the presence of 1,1,2-trichloroethane, a novel procedure for the Pd-C catalytic N-debenzylation of benzylamines was established. The method proceeded in a synergistic catalytic system and directly gave the products as crystal amine hydrochlorides in practically quantitative yields.
Nonracemic Betti Base as a New Chiral Auxiliary: Application to Total Syntheses of Enantiopure (2S,6R)-Dihydropinidine and (2S,6R)-Isosolenopsins
摘要:
Total syntheses of enantiopure alkaloidal natural products (2S,6R)-dihydropinidine (as hydrochloride) and (2S,6R)isosolenopsins (as hydrochlorides) were achieved in four steps and in 80-82% total yields by using a synthetic strategy of the formation-cleavage of 1,3-oxazinane. (S)-Betti base was proved to be an excellent chiral auxiliary and a novel Pd/C catalyzed N-debenzylation straightforward to amine hydrochloride was developed in the presence of CH2Cl2.