944249-84-7Relevant academic research and scientific papers
Oxidative alkoxycarbonylation of terminal alkenes with carbazates
Su, Yu-Han,Wu, Zhao,Tian, Shi-Kai
, p. 6528 - 6530 (2013)
A range of terminal alkenes smoothly underwent palladium-catalyzed oxidative alkoxycarbonylation with carbazates under an oxygen atmosphere to afford structurally diverse α,β-unsaturated esters in moderate to good yields with excellent regioselectivity and E selectivity.
Tandem Palladium and Isothiourea Relay Catalysis: Enantioselective Synthesis of α-Amino Acid Derivatives via Allylic Amination and [2,3]-Sigmatropic Rearrangement
Spoehrle, Stéphanie S. M.,West, Thomas H.,Taylor, James E.,Slawin, Alexandra M. Z.,Smith, Andrew D.
, p. 11895 - 11902 (2017/09/07)
A tandem relay catalytic protocol using both Pd and isothiourea catalysis has been developed for the enantioselective synthesis of α-amino acid derivatives containing two stereogenic centers from readily accessible N,N-disubstituted glycine aryl esters and allylic phosphates. The optimized process uses a bench-stable succinimide-based Pd precatalyst (FurCat) to promote Pd-catalyzed allylic ammonium salt generation from the allylic phosphate and the glycine aryl ester. Subsequent in situ enantioselective [2,3]-sigmatropic rearrangement catalyzed by the isothiourea benzotetramisole forms syn-α-amino acid derivatives with high diastereo- and enantioselectivity. This methodology is most effective using 4-nitrophenylglycine esters and tolerates a variety of substituted cinnamic and styrenyl allylic ethyl phosphates. The use of challenging unsymmetrical N-allyl-N-methylglycine esters is also tolerated under the catalytic relay conditions without compromising stereoselectivity.
Synthesis of (-)-conocarpan by two routes based on radical cyclization and establishment of its absolute configuration
Clive, Derrick L. J.,Stoffman, Elia J. L.
supporting information; experimental part, p. 1831 - 1842 (2008/10/09)
Two independent routes for the total synthesis of the bioactive neolignan (-)-conocarpan are described. The first (98% ee) is based on formal radical cyclization onto a benzene ring, and involves a 5-exo-trigonal closure onto a double bond restrained within a 6-membered ring. The second route (88% ee), which is shorter, is based on 5-exo-trigonal cyclization of an aryl radical onto a pendant terminal double bond. The two routes differ in their degree of stereoselectivity. The absolute configuration originally assigned to (+)-conocarpan had previously been called into question on the basis of empirical chiroptical rules; the present chemical work confirms the need for revision, and the assigned absolute configurations of several compounds correlated with (+)-conocarpan must also be changed. The Royal Society of Chemistry.
Total synthesis of (-)-conocarpan and assignment of the absolute configuration by chemical methods
Clive, Derrick L. J.,Stoffman, Elia J. L.
, p. 2151 - 2153 (2008/02/08)
(-)-Conocarpan (1) was synthesized by a method based on radical cyclization, and the absolute configuration was established by chemical degradation; the original 2R,3R-assignment to (+)-conocarpan should be reversed, as suggested by a later chiroptical study of model 2,3-dihydrobenzofurans. The Royal Society of Chemistry.
