5663-85-4Relevant academic research and scientific papers
Unusually High Reactivity of the C-Si Bond in the Lewis Acid Mediated Reactions of (E)-1-(Trimethylsilyl)-2-(isopropylthio)ethylene with Carbonyl Electrophiles
Bonini, Bianca F.,Comes-Franchini, Mauro,Fochi, Mariafrancesca,Mazzanti, Germana,Ricci, Alfredo
, p. 681 - 682 (1997)
In the reaction with benzaldehyde and with cyclic α,β-unsaturated ketones in the presence of Lewis acids. (E)-1-(trimethylsilyl)-2-(isopropylthio)ethylene exhibits enhanced reactivity compared to that of (E)-1-(trimethylsilyl)-hept-1-ene. Moreover dependi
One-Pot Catalytic Enantioselective Synthesis of 2-Pyrazolines
Thomson, Connor J.,Barber, David M.,Dixon, Darren J.
supporting information, p. 2469 - 2473 (2019/02/01)
A scalable, one-pot, enantioselective catalytic synthesis of 2-pyrazolines from beta-substituted enones and hydrazines is described. Pivoting on a two-stage catalytic Michael addition/condensation strategy, the use of an aldehyde to generate a suitable hydrazone derivative of the hydrazine was found to be key for curtailing background reactivity and tuning the catalyst-controlled enantioselectivity. The new synthetic method is easy to perform, uses a new and readily prepared cinchona-derived bifunctional catalyst, is broad in scope, and tolerates a range of functionalities with high enantioselectivity (up to >99:1 e.r.). The significant scalability of this methodology was demonstrated with the synthesis of more than 80 grams of a pyrazoline product with 89 % catalyst recovery.
Stereoselective synthesis of either (E)- or (Z)-silyl enol ether from the same acyclic α,β-unsaturated ketone using cationic rhodium complex-catalyzed 1,4-hydrosilylation
Onodera, Gen,Hachisuka, Ryosuke,Noguchi, Tomomi,Miura, Hiroki,Hashimoto, Toru,Takeuchi, Ryo
supporting information, p. 310 - 313 (2014/01/06)
The stereoselective synthesis of either (E)- or (Z)-silyl enol ether from the same acyclic α,β-unsaturated ketone is reported. Highly (Z)-selective conditions were the use of [Rh(cod)2]BF 4/DPPE at room temperature with no solvent, whereas (E)-selective conditions were the use of [Rh(cod)2]BF4/P(1-Nap) 3 (1-Nap = 1-naphthyl) under refluxing dichloromethane.
Structural study-guided development of versatile phase-transfer catalysts for asymmetric conjugate additions of cyanide
Provencher, Brian A.,Bartelson, Keith J.,Liu, Yan,Foxman, Bruce M.,Deng, Li
, p. 10565 - 10569 (2011/12/05)
Unprecedented phase-transfer catalysts for the first example of an organocatalytic asymmetric conjugate addition of cyanide with acetone cyanohydrin are reported (see scheme). Utilizing an accessible cupreidinium salt and a cyanation reagent suitable for industrial scale, this reaction holds significant promise for practical asymmetric synthesis. The catalysts were developed as a result of key structural insights gained by X-ray analysis. Copyright
Palladium-catalyzed cross-coupling reactions of organogold(I) reagents with organic electrophiles
Pena-Lopez, Miguel,Ayan-Varela, Miguel,Sarandeses, Luis A.,Perez Sestelo, Jose
supporting information; experimental part, p. 9905 - 9909 (2010/10/19)
The palladium-catalyzed cross-coupling reaction of organogold(I) reagents (alkyl, alkenyl, aryl, and alkynyl) with organic electrophiles, such as aryl and alkenyl halides, aryl triflates, benzyl bromide, and benzoyl chloride is reported. The reaction takes place, under palladium catalysis, at room temperature with short reaction times to give the corresponding cross-coupling products in high yields.
Development of a merged conjugate addition/oxidative coupling sequence. Application to the enantioselective total synthesis of metacycloprodigiosin and prodigiosin R1
Clift, Michael D.,Thomson, Regan J.
supporting information; experimental part, p. 14579 - 14583 (2010/03/05)
A merged conjugate addition/oxidative coupling sequence that represents an efficient strategy for preparing structurally diverse pyrroles has been developed. Success of the method hinged upon the controlled oxidative coupling of unsymmetrical silyl bis-en
The cation exchange resin-promoted coupling of alkynes with aldehydes: one-pot synthesis of α,β-unsaturated ketones
Yadav,Subba Reddy,Vishnumurthy
, p. 4498 - 4500 (2008/09/21)
Alkynes undergo smooth coupling with aldehydes in the presence of Amberlyst-15 at room temperature to produce the corresponding α,β-unsaturated ketones in high yields with E-geometry. The use of an inexpensive, readily available, and recyclable cation exchange resin makes this method quite simple and convenient.
Carbonylative addition of arylboronic acids to terminal alkynes: A new catalytic access to α,β-unsaturated ketones
Dheur, Julien,Sauthier, Mathieu,Castanet, Yves,Mortreux, Andre
, p. 2499 - 2506 (2008/09/19)
The carbonylative addition of arylboronic acids to terminal alkynes under mild conditions affords (E)-α,β-unsaturated ketones with good yields. The reaction was achieved with chloro(1,5-cyclooctadiene)rhodium(I) dimer or chlorodicarbonylrhodium(I) dimer a
Ytterbium triflate promoted coupling reaction between aryl alkynes and aldehydes
Curini, Massimo,Epifano, Francesco,Maltese, Federica,Rosati, Ornelio
, p. 552 - 554 (2007/10/03)
A simple and efficient solvent-free coupling reaction affording regioselectively trans-α,β-enones from aryl alkynes and aldehydes catalysed by Yb(OTf)3 hydrate is described.
Iodine(V) reagents in organic synthesis. Part 4. o-Iodoxybenzoic acid as a chemospecific tool for single electron transfer-based oxidation processes
Nicolaou,Montagnon,Baran,Zhong
, p. 2245 - 2258 (2007/10/03)
o-Iodoxybenzoic acid (IBX), a readily available hypervalent iodine(V) reagent, was found to be highly effective in carrying out oxidations adjacent to carbonyl functionalities (to form α, β-unsaturated carbonyl compounds) and at benzylic and related carbon centers (to form conjugated aromatic carbonyl systems). Mechanistic investigations led to the conclusion that these new reactions are initiated by single electron transfer (SET) from the substrate to IBX to form a radical cation which reacts further to give the final products. Fine-tuning of the reaction conditions allowed remarkably selective transformations within multifunctional substrates, elevating the status of this reagent to that of a highly useful and chemoselective oxidant.
