440369-01-7Relevant academic research and scientific papers
Enantiocontrol over Acyclic Quaternary Stereocenters by Acylative Organocatalyzed Kinetic Resolution
Bressy, Cyril,Charles, Laurence,Liu, Xueyang,Monnier, Valérie,Pons, Jean-Marc,Quintard, Adrien
supporting information, (2022/03/01)
In the present paper, we described the efficient enantioselective kinetic resolution (KR) of racemic diastereocontrolled secondary alcohols bearing a quaternary stereocenter using a commercially available chiral isothiourea organocatalyst. This methodology is a general KR leading to the enantiocontrol of acyclic quaternary stereocenter with high levels of stereoselectivity (s up to 185) on a large scope. The hydroxyl function can easily serve as a traceless group by oxidation or reduction process.
Chiral phosphoramide-catalyzed enantioselective addition of allylic trichlorosilanes to aldehydes. Preparative studies with bidentate phosphorus-based amides
Denmark, Scott E.,Fu, Jiping,Lawler, Michael J.
, p. 1523 - 1536 (2007/10/03)
On the basis of the mechanistic insight that more than one Lewis basic moiety (phosphoramide) is involved in the rate- and stereochemistry-determining step of enantioselective allylation, bidentate chiral phosphoramides were developed. Different chiral phosphoramide moieties were connected by tethers of methylene chains of varying length. The rate and enantioselectivity of allylation with allyltrichlorosilane promoted by the bidentate phosphoramides was found to be highly dependent on the tether length. A new phosphoramide based on a 2,2′-bispyrrolidine skeleton has been designed and afforded good yield, efficient turnover, and high enantioselectivity in allylation reactions. The synthesis of enantiopure 2,2′-bispyrrolidine was easily accomplished on large scale by photodimerization of pyrrolidine followed by resolution with L(or D)-tartaric acid. The scope of the allylation reaction was examined with variously substituted allylic trichlorosilanes and unsaturated aldehydes. This method has been applied to the construction of stereogenic, quaternary centers by the addition of unsymmetrically γ-disubstituted allylic trichlorosilanes.
Asymmetric Construction of Quaternary Centers by Enantioselective Allylation: Application to the Synthesis of the Serotonin Antagonist LY426965
Denmark, Scott E.,Fu, Jiping
, p. 1951 - 1953 (2007/10/03)
(Matrix Presented) Catalytic enantioselective allylation with a chiral bisphosphoramide was applied to the synthesis of LY426965, a serotonin antagonist. The key step, addition of a 3,3-disubstituted allyltrichlorosilane to benzaldehyde, provided the addu
