58879-44-0Relevant academic research and scientific papers
Regioselective Rh-Catalyzed Hydroformylation of 1,1,3-Trisubstituted Allenes Using BisDiazaPhos Ligand
Eshon, Josephine,Landis, Clark R.,Schomaker, Jennifer M.
, p. 9270 - 9278 (2017/09/22)
The efficient hydroformylation of 1,1,3-trisubstituted allenes is accomplished with low loadings of a Rh catalyst supported by a BisDiazaPhos (BDP) ligand. The ligand identity is key to achieving high regioselectivity, while the mild reaction conditions m
Gold-catalyzed isomerization of unactivated allenes into 1,3-dienes under ambient conditions
Ting, Chun-Ming,Hsu, Yi-Ling,Liu, Rai-Shung
supporting information; experimental part, p. 6577 - 6579 (2012/07/31)
We have developed a gold-catalyzed isomerization of unactivated allenes into 1,3-dienes with nitrosobenzene as an additive. This reaction proceeded almost exclusively at room temperature for highly substituted allenes. The utility of this reaction is manifested by the development of one-pot [4+2]-cycloaddition of allenes and reactive alkenes.
Copper-catalyzed enantioselective propargylic amination of propargylic esters with amines: Copper-allenylidene complexes as key intermediates
Hattori, Gaku,Sakata, Ken,Matsuzawa, Hiroshi,Tanabe, Yoshiaki,Miyake, Yoshihiro,Nishibayashi, Yoshiaki
supporting information; experimental part, p. 10592 - 10608 (2010/09/10)
The scope and limitations of the copper-catalyzed propargylic amination of various propargylic esters with amines are presented, where optically active diphosphines such as Cl-MeO-BIPHEP and BINAP work as good chiral ligands. A variety of secondary amines are available as nucleophiles for this catalytic reaction to give the corresponding propargylic amines with a high enantioselectivity. The results of some stoichiometric and catalytic reactions indicate that the catalytic amination proceeds via copper-allenylidene complexes formed in situ, where the attack of amines to the electrophilic γ-carbon atom in the allenylidene complex is an important step for the stereoselection. Investigation of the relative rate constants for the reaction of several para-substituted propargylic acetates with N-methylanilines reveals that the formation of the copper-allenylidene complexes is involved in the rate-determining step. The result of the density functional theory calculation on a model reaction also supports the proposed reaction pathway involving copper-allenylidene complexes as key intermediates. The catalytic procedure presented here provides a versatile and direct method for the preparation of a variety of chiral propargylic amines.
Palladium-Catalyzed Propargylic vs. Allylic Alkylation
Keinan, Ehud,Bosch, Eric
, p. 4006 - 4016 (2007/10/02)
The relative reactivities of allylic propargylic acetates toward palladium(0)-catalyzed substitution by various nucleophiles were studied bu using three types of model substrates: (a) monofunctional allylic and propargylic acetates with similar structural properties; (b) a bifunctional substrate containing both allyl and propargyl functionalities with no apparent interaction between them; (c) conjugated bifunctional systems, in which the two functionalities may interact with one another.Palladium(0)-catalyzed substitution of propargylic acetates by various carbon nucleophiles was found to be less general than the analogous substitution of allylic acetates.Three modes of reactivity were observed, corresponding to three groups of nucleophiles; (a) stabilized carboanions such as sodium dimethyl malonate, which do not react with propargylic acetates but react readily with allylic acetates; (b) nonstabilized organometallics such as phenylzinc chloride, which react with propargylic and allylic acetates at comparable rates (reaction with the former yielding the allenic product exlusively); and (c) allyl- and allenylstannanes, which react with allylic acetates but do not react with isolated propargylic acetates (except for special cases where the propargylic acetate is also an allylic one).Certain similarities between regioselectivity phenomena in organopalladium and organocopper chemistry are discussed.
