226900-30-7Relevant academic research and scientific papers
Synthesis and competency of a novel dicationic phase-transfer catalyst
Kowtoniuk, Walter E.,Rueffer, Michelle E.,MacFarland, Darren K.
, p. 151 - 154 (2004)
Synthesis and characterization of a novel phase-transfer catalyst, 6,6′ di(triethylammoniummethyl)-2,2′-dihexyloxybi-1,1′- naphthalene, are reported. Preliminary catalytic studies on the alkylation of a glycine derivative show the catalyst to be an effect
Enantioselective alkylation using a new C3 symmetric amine-based chiral phase-transfer catalyst
Mase, Nobuyuki,Ohno, Takahiro,Hoshikawa, Naoki,Ohishi, Kazuhiro,Morimoto, Hironao,Yoda, Hidemi,Takabe, Kunihiko
, p. 4073 - 4075 (2003)
A new C3 symmetric amine-based chiral phase-transfer catalyst was synthesized. Application of the chiral PTC (1 mol%) in the alkylation of a tert-butyl glycinate-benzophenone Schiff base under mild reaction conditions provided an alkylated prod
Stereoselective deconjugation of macrocyclic α,β-unsaturated esters by sequential amidation and olefin transposition: Application to enantioselective phase-transfer catalysis
Homberg, Alexandre,Hrdina, Radim,Vishe, Mahesh,Guénée, Laure,Lacour, Jér?me
, p. 6905 - 6910 (2019)
The stereoselective synthesis of chiral macrocycles bearing two aliphatic amide functional groups is reported. After the amidation mediated by TBD, a guanidine derivative, the olefin transposition step is performed with a slight excess of t-BuOK. The products are afforded in moderate to good combined yields (up to 59%) and with an excellent syn diastereoselectivity (dr > 49:1). Introducing enantiopure α-branched substituents was possible and it resulted in mixtures of diastereomers, which could be tested as phase-transfer catalysts using the formation of a phenylalanine analog as a test reaction (up to 43% ee). A clear matched-mismatched situation was observed in the two diastereomeric series.
Directing the Cation Recognition Ability of Calix[4]arenes toward Asymmetric Phase-Transfer Catalysis
De Simone, Nicola Alessandro,Schettini, Rosaria,Talotta, Carmen,Gaeta, Carmine,Izzo, Irene,Della Sala, Giorgio,Neri, Placido
, p. 5649 - 5659 (2017/10/16)
The recognition abilities of chiral calixarene hosts toward alkali cation guests have been exploited for the first time in asymmetric phase-transfer catalysis. The binding affinities of a series of chiral α-methylbenzylamine-derived calix[4]arene-amides toward Na+ guest have been determined by 1H NMR spectroscopic titration experiments. The good apparent association constant values are consistent with the macrocycles' catalytic efficiency in the asymmetric alkylation reaction of N-(diphenylmethylene)glycine esters under phase-transfer conditions.
Phase-Transfer Catalysis via a Proton Sponge: A Bifunctional Role for Biscyclopropenimine
Belding, Lee,Stoyanov, Peter,Dudding, Travis
, p. 553 - 558 (2016/01/25)
The use of a bis(diisopropylamino)cyclopropenimine-substituted bis-protonated proton sponge as a bifunctional phase-transfer catalyst is reported. Experimental studies and DFT calculations suggest it operates simultaneously as a hydrogen bond donor and a
N-Heterocyclic olefins as efficient phase-transfer catalysts for base-promoted alkylation reactions
Blümel, Marcus,Crocker, Reece D.,Harper, Jason B.,Enders, Dieter,Nguyen, Thanh V.
supporting information, p. 7958 - 7961 (2016/07/06)
N-Heterocyclic olefins (NHOs) have very recently emerged as efficient promoters for several chemical reactions due to their strong Br?nsted/Lewis basicities. Here we report the novel application of NHOs as efficient phase-transfer organocatalysts for synt
Rate Acceleration of Solid-Liquid Phase-Transfer Catalysis by Rotor-Stator Homogenizer
Kano, Taichi,Aota, Yusuke,Maruoka, Keiji
supporting information, p. 2996 - 2999 (2016/09/16)
A rotor-stator homogenizer was found to be an effective mixing tool that accelerated solid-liquid phase-transfer reactions. In the asymmetric alkylation under phase-transfer conditions using the homogenizer, a considerably high turnover frequency was observed. (Figure presented.).
A Simple Chiral Cu(II) Complex as an Effective Phase-Transfer Catalyst for the Enantioselective Alkylation of Dissymmetric Glycinate Ketimines
Bafqiren, Hanane,Zouihri, Hafid,Gmouh, Said,Jamal Eddine, Jamal
, p. 944 - 950 (2015/11/16)
Catalytic asymmetric benzylation of a dissymmetric tert-butylglycinate ketimine, incorporating 1-naphthyl and phenyl groups as the Schiff base substituents, under phase-transfer conditions was investigated. It was interesting to note that the sense of asymmetric induction of the alkylation of Z-imine stereoisomer is opposite to that of the corresponding E stereoisomer with a similar degree of enantioselectivity. More interestingly, the chiral Cu(II) complex of the Schiff base derived from (R)-2-phenylglycinol and 2-hydroxy-1-naphthaldehyde was found to catalyze the same reaction under solid-liquid conditions with comparable enantioselectivity (up to 60% ee) with respect to known cinchona alkaloid catalysts. The solvent/base-system parameter was shown to control the optimal catalytic activity. Chirality 27:944-950, 2015.
Phase-transfer and other types of catalysis with cyclopropenium ions
Bandar, Jeffrey S.,Tanaset, Anont,Lambert, Tristan H.
supporting information, p. 7365 - 7368 (2015/05/13)
Abstract This work establishes the cyclopropenium ion as a viable platform for efficient phase-transfer catalysis of a diverse range of organic transformations. The amenability of these catalysts to large-scale synthesis and structural modification is demonstrated. Evaluation of the molecular structure of an optimal catalyst reveals some unique structural features of these systems. Finally, a discussion of electronic charge distribution underscores an important consideration for catalyst design. Aromatic ions: Tris(dialkylamino)cyclopropenium ions are shown to be effective carbocationic phase-transfer catalysts for a variety of mainstay transformations. The cyclopropenium platform is shown to be modular and accessible on scale. An X-ray structure and electron-density map revealed some unique features of this architecture (see scheme).
Redefining q: Quaternary ammonium cross sectional area (XSA) as a general descriptor for transport-limiting PTC rate approximations
Denmark,Henle
, p. 2211 - 2218 (2015/03/30)
The relationships of several key molecular descriptors with the rate of the O'Donnell alkylation under phase transfer catalysis (PTC) have been investigated. The most common parameter used to predict PTC rates, the ammonium ion accessibility, q, is define
