Synthesis of Bicyclic Guanidines via Cascade Hydroamination/Michael Additions of Mono-<i>N</i>-acryloylpropargylguanidines
作者:Ki-Hyeok Kwon、Catherine M. Serrano、Michael Koch、Louis R. Barrows、Ryan E. Looper
DOI:10.1021/ol502691w
日期:2014.12.5
A cascade silver(I)-catalyzed hydroamination/Michael addition sequence has been developed to deliver highly substituted bicyclic guanidines. This transformation gives rise to geometrically and constitutionally stable ene-guanidines and generates a remote stereocenter with moderate to high diastereoselectivity.
Hypervalent Iodine(III)-Mediated Cascade Cyclization of Propargylguanidines and Total Syntheses of Kealiinine B and C
作者:Guilong Tian、Pavel Fedoseev、Erik V. Van der Eycken
DOI:10.1002/chem.201700934
日期:2017.4.19
An oxidative cascadecyclization of propargylguanidines promoted by phenyliodonium diacetate (PIDA) was developed. The protocol provides an efficient route for the synthesis of the alkaloids kealiininesB and C as well as homologues. The difference in the electronic nature of the acetylene substituent resulted in two ways of the cyclization. A plausible mechanism is proposed based on the experimental