... X-Ray crystal structure of borane adduct of ligand 1. This adduct is stable to air, moisture and even column chromatography pro-R N H O ... O (S) (R) ...
... ACS PRF #49493-UR1 MeO PCy2 Ligand 1 X-Ray crystal structure of cyclized product, confirming configuration of chiral center and axis ...
... California Institute of Technology Proposed mechanism: Lewis acid and Lewis acid-assisted Brønsted acid cooperativity. Development of a ...
Enantioselective α-Arylation of O
Mar 6, 2017 - Transition-metal-catalyzed asymmetric α-arylation of carbonyl compounds is a widely studied method for CâC bond formation. Recently, the α-arylation of α-fluoro ketones has been reported, including enantioselective α-arylation of
May 24, 2017 - Department of Process Research & Development, Merck & Company, Incorporated, P.O. Box 2000, Kenilworth, New Jersey 07065, United States. J. Am. Chem. Soc. , 2017, 139 (24), pp 8337â8345 ..... Crystallographic data (CIF). Procedures a
Feb 8, 2018 - Herein we reported an efficient palladium-catalyzed enantioselective arylation of both alkyl and aryl sulfenate anions to deliver various chiral sulfoxides in good yields (up to 98%) with excellent enantioselectivities (up to 99% ee) by
This protocol provides an efficient access to valuable chiral tetrasubstituted 1,2,5-thiadiazoline 1,1-dioxides in high yields with excellent enantioselectivities of up ...
Ya-Jing Chen , Ya-Heng Chen , Chen-Guo Feng , and Guo-Qiang Lin ... Balraj Gopula , Chien-Wei Chiang , Way-Zen Lee , Ting-Shen Kuo , Ping-Yu Wu , Julian ...
Jul 13, 2016 - *E-mail for L.H.: [email protected]., *E-mail for M.L.: [email protected]., ... Gongming Zhu , Guangjun Bao , Yiping Li , Wangsheng Sun , Jing Li , Liang Hong , Rui Wang ... Chen, Xu, Zhou, Chung, and Tang.
Development of Enantioselective Nitrogen Arylation Reactions Russell D. Viirre Dept. of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
pro-R R N H
O
O
pro-S R N H
Br
pro-R O R N H
"(R)-MOP palladium(0) complex" oxidative addition
(R)-MOPn
PPh2 OMe
O pro-S N H
R base (R)-MOP
Pd
Br achiral, with enantiotopic amide groups O
R
O
O
N (R)-MOPn
Pd
(R)
N H
R R
O
O
R
O
N N H
diastereomeric intermediates (formed unequally)
ACS PRF #49493-UR1
base • HBr
single enantiomer, with diastereotopic amide groups
(S)
Pd
(R)-MOPn
reductive elimination R
N
(R)
R R NH
HN
O (S)
O N
enantiomeric products in yields up to 99% and enantiomeric excesses up to 96%