108380-28-5Relevant academic research and scientific papers
Iridium-Catalyzed C-C Coupling of a Simple Propargyl Ether with Primary Alcohols: Enantioselective Homoaldol Addition via Redox-Triggered (Z)-Siloxyallylation
Liang, Tao,Zhang, Wandi,Krische, Michael J.
, p. 16024 - 16027 (2015)
A chiral iridium complex formed in situ from [Ir(cod)Cl]2 and (R)-H8-BINAP is found to catalyze the direct enantioselective C-C coupling of a simple propargyl ether, TIPSOCH2C-CH, with primary alcohols to form γ-hydroxy (Z)-enol silanes with uniformly high enantioselectivity and complete alkene (Z)-stereoselectivity. As corroborated by deuterium labeling studies, these studies represent the first examples of 1,2-hydride shift-enabled π-allyl formation in the context of iridium catalysis.
Carboxyl Group-Directed Iridium-Catalyzed Enantioselective Hydrogenation of Aliphatic ?-Ketoacids
Li, Mao-Lin,Li, Yao,Li, Yi-Hao,Pan, Jia-Bin,Song, Song,Zhou, Qi-Lin,Zhu, Shou-Fei
, p. 10032 - 10039 (2020/10/18)
Although the transition metal-catalyzed asymmetric hydrogenation of aromatic ketones has been extensively explored, the enantioselective hydrogenation of aliphatic ketones remains a challenge because chiral catalysts cannot readily discriminate between the re and si faces of these ketones. Herein, we report a carboxyl-directing strategy for the asymmetric hydrogenation of aliphatic ?-ketoacids. With catalysis by iridium complexes bearing chiral spiro phosphino-oxazoline ligands, hydrogenation of aliphatic ?-ketoacids afforded chiral ?-hydroxylacids with high enantioselectivity (up to 99% ee). Mechanistic studies revealed that the carboxyl group of the substrate directs hydrogen transfer and ensures high enantioselectivity. Density functional theory calculations suggested the occurrence of chiral induction involving a hydrogen-hydrogen interaction between a hydride on the iridium atom and the substituent on the oxazoline ring of the ligand, and on the basis of the calculations, we proposed a catalytic cycle involving only Ir(III), which differs from the Ir(III)/Ir(V) catalytic cycle that operates in the hydrogenation of α,β-unsaturated carboxylic acids.
A direct method for the conversion of terminal epoxides into γ-butanolides
Movassaghi, Mohammad,Jacobsen, Eric N.
, p. 2456 - 2457 (2007/10/03)
A new and efficient process for the conversion of terminal epoxides to γ-butanolides is described involving Lewis acid promoted epoxide ring-opening by 1-morpholino-2-trimethylsilyl acetylene. Addition of a terminal epoxide to a solution of the ynamine an
Synthesis of (S)-Hydroxyethyl-γ-butyrolctone and Its Application to the Synthesis of R(+)-γ-Caprolactone
Gurjar, Mukund K.,Patil, Vijay J.
, p. 596 - 599 (2007/10/02)
Synthesis of S-hydroxyethyl-γ-butyrolactone, as a chiral building block for the natural product synthesis, is described.Its utility in the synthesis of naturally occurring R(+)-caprolactone, a pheromone of Trogoderma species of dermestid beetles, is repor
