78173-73-6Relevant academic research and scientific papers
Phosphine-Catalyzed Reaction between 2-Aminobenzaldehydes and Dialkyl Acetylenedicarboxylates: Synthesis of 1,2-Dihydroquinoline Derivatives and Toward the Development of an Olefination Reaction
Han, Xu,Saleh, Nidal,Retailleau, Pascal,Voituriez, Arnaud
supporting information, p. 4584 - 4588 (2018/08/09)
A series of 1,2-dihydroquinolines were synthesized in good to excellent yields by reacting 2-aminobenzaldehyde derivatives and dialkyl acetylenedicarboxylates with catalytic amounts of phosphine. This reaction was rendered catalytic by the selective in situ phosphine oxide reduction with the use of phenylsilane. Furthermore, with the same starting materials and with an additional role of the reducing agent, a new olefination reaction was discovered. Hydrogen/deuterium (H/D) exchange experiments revealed the possible mechanism of this reaction.
Novel Base-Free Catalytic Wittig Reaction for the Synthesis of Highly Functionalized Alkenes
Schirmer, Marie-Luis,Adomeit, Sven,Spannenberg, Anke,Werner, Thomas
supporting information, p. 2458 - 2465 (2016/02/12)
A highly efficient catalyst system for base-free catalytic Wittig reactions has been developed and optimized. Initially, several potential (pre)catalysts as well as different silanes as reducing agents were screened. A system based on a readily available
First Base-Free Catalytic Wittig Reaction
Schirmer, Marie-Luis,Adomeit, Sven,Werner, Thomas
supporting information, p. 3078 - 3081 (2015/06/30)
The first base-free catalytic Wittig reaction utilizing readily available Bu3P (5 mol %) as an organocatalyst is reported. The initial Michael addition of the phosphine to a suitable acceptor substituted alkene ultimately results in the formation of an ylide which is subsequently converted with an aldehyde. The presented 1H NMR studies actually reveal evidence for the Michael addition and proposed ylide formation. Under the optimized reaction conditions various maleates and fumarates were converted with aromatic, heteroaromatic, and aliphatic aldehydes to evaluate the scope and limitations of this unprecedented reaction. Notably, maleates and fumarates react in a stereoconvergent fashion. The corresponding products were obtained in up to 95% isolated yield and E/Z-selectivities up to 99:1.
Asymmetric dihydroxylation of β,γ-unsaturated carboxylic esters with trisubstituted C=C bonds - Enantioselective syntheses of trisubstituted γ-butyrolactones
Kapferer, Tobias,Brueckner, Reinhard
, p. 2119 - 2133 (2007/10/03)
β,γ-Unsaturated esters with stereodefined trisubstitued C=C double bonds were prepared by the Arndt-Eistert homologation of α,β-unsaturated carboxyl halides, by two-step methoxycarbonylation of allylbarium reagents, by deconjugation of α,β-unsaturated esters, and by Horner-Wadsworth-Emmons variants of the Stobbe condensation. Sharpless asymmetric dihydroxylation of the β,γ-unsaturated esters, followed by spontaneous cyclization, afforded β-hydroxy-γ-lactones in moderate to good yields and with enantiomeric excesses of up to 97 %. Similarly, tetrahydroxy-γ-lactones were obtained from diunsaturated esters; these lactones were converted into a bislactone and an unsaturated β-hydroxy γ-lactone. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
Pd(II)-Schiff base complexes heterogenised on MCM-41 and delaminated zeolites as efficient and recyclable catalysts for the heck reaction
Gonzalez-Arellano,Corma,Iglesias,Sanchez
, p. 1758 - 1764 (2007/10/03)
We present a widely applicable approach for the preparation of Pd-complexes supported on silica-based mesoporous and laminar inorganic solids (silica gel, purely siliceous and acidic MCM-41, and delaminated zeolites ITQ-2 and ITQ-6) which involves the use of the Schiff bases 2-tert-butyl-4-methyl-6{(E)-[(2S)-1- (1-arylmethyl)pyrrolidinyl]imino}methylphenol (aryl = phenyl, 1-naphthyl, 2-naphthyl) as anchored ligands. As an extension of our research in recyclable catalytic systems we report results demonstrating the reactivity and recyclability of these systems for the Heck reaction (in a biphasic mode using ethylene glycol and toluene) and Suzuki coupling under phosphine-free conditions. The complexes are insensitive to oxygen or moisture, and no change of their activity was observed when exposed to an open system during the usual operation. No palladium black was observed after an extended reaction time and no residual palladium was detected from the filtrate at the end of the reaction.
NEW YLIDE ANIONS. A VINYL ANION EQUIVALENT FOR SUBSTITUTED FUMARATE ESTERS
Cooke, Manning P.
, p. 381 - 384 (2007/10/02)
A new type of ylide anion is reported which upon alkylation and elimination of triphenylphosphine serves as a vinyl anion equivalent.
