869376-22-7Relevant academic research and scientific papers
Mechanism of NHC-Catalyzed Conjugate Additions of Diboron and Borosilane Reagents to α,β-Unsaturated Carbonyl Compounds
Wu, Hao,Garcia, Jeannette M.,Haeffner, Fredrik,Radomkit, Suttipol,Zhugralin, Adil R.,Hoveyda, Amir H.
, p. 10585 - 10602 (2015/09/28)
Broadly applicable enantioselective C-B and C-Si bond-forming processes catalyzed by an N-heterocyclic carbene (NHC) were recently introduced; these boryl and silyl conjugate addition reactions (BCA and SCA, respectively), which proceed without the need f
An Insoluble Copper(II) Acetylacetonate-Chiral Bipyridine Complex that Catalyzes Asymmetric Silyl Conjugate Addition in Water
Kitanosono, Taku,Zhu, Lei,Liu, Chang,Xu, Pengyu,Kobayashi, Shu
supporting information, p. 15422 - 15425 (2015/12/26)
Acicular purplish crystals were obtained from Cu(acac)2 and a chiral bipyridine ligand. Although the crystals were not soluble, they nevertheless catalyzed asymmetric silyl conjugate addition of lipophilic substrates in water. Indeed, the reactions proceeded efficiently only in water; they did not proceed well either in organic solvents or in mixed water/organic solvents in which the catalyst/substrates were soluble. This is in pronounced contrast to conventional organic reactions wherein the catalyst/substrates tend to be in solution. Several advantages of the chiral Cu(II) catalysis in water over previously reported catalyst systems have been demonstrated. Water is expected to play a prominent role in constructing and stabilizing sterically confined transition states and accelerating subsequent protonation to achieve high yields and enantioselectivities.
Simple chiral diene ligands provide high enantioselectivities in transition-metal-catalyzed conjugate addition reactions
Okamoto, Kazuhiro,Hayashi, Tamio,Rawal, Viresh H.
supporting information; experimental part, p. 4387 - 4389 (2009/05/30)
(Chemical Equation Presented) Chiral dienes possessing the bicyclo[2.2.2]octadiene framework were prepared readily through the [4 + 2] cycloaddition of (R)-α-phellandrene with methyl propiolate as the key step. Diene 9, substituted with a tertiary alcohol
Cu-catalyzed asymmetric conjugate additions of dialkyl- and diarylzinc reagents to acyclic β-silyl-α,β-unsaturated ketones. Synthesis of allylsilanes in high diastereo- and enantiomeric purity
Kacprzynski, Monica A.,Kazane, Stephanie A.,May, Tricia L.,Hoveyda, Amir H.
, p. 3187 - 3190 (2008/02/11)
A readily available and simple (MW = 444.5 g/mol) valine-based chiral phosphine is used to promote highly efficient catalytic asymmetric conjugate additions of dialkyl- and diarylzinc reagents to acyclic β-silyl-α, β-unsaturated ketones. The catalytic asy
Carbon-carbon bond-forming enantioselective synthesis of chiral organosilicon compounds by rhodium/chiral diene-catalyzed asymmetric 1,4-addition reaction
Shintani, Ryo,Okamoto, Kazuhiro,Hayashi, Tamio
, p. 4757 - 4759 (2007/10/03)
(Chemical Equation Presented) A new synthetic method for chiral organosilicon compounds through a rhodium-catalyzed asymmetric 1,4-addition of arylboronic acids to β-silyl α,β-unsaturated carbonyl compounds has been developed. By employing (R,R)-Bn-bod * as a ligand, a range of arylboronic acids can be coupled with these substrates in very high enantiomeric excess. The resulting β-silyl 1,4-adducts can be converted to β-hydroxy carbonyl compounds or allylsilanes while retaining their stereochemical information.
Catalytic asymmetric synthesis of β-hydroxy ketones by palladium-catalyzed asymmetric 1,4-disilylation of α,β-unsaturated ketones
Matsumoto, Yonetatsu,Hayashi, Tamio,Ito, Yoshihiko
, p. 335 - 346 (2007/10/02)
1,4-Disilylation of β,β-unsaturated ketones with 1,1-dichloro-1-phenyl-2,2,2-trimethyldisilane proceeded in the presence of phosphine-palladium catalysts in benzene. High enantio-selectivity (up to 92%) was observed in the disilylation with dichloro[(R)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl] palladium(II) as a catalyst (0.5 mol %). The disilylation products, 1-(trimethyisilyloxy)-3-(dichlorophenylsilyl)propenes, were readily converted into optically active α-unsubstituted or anti α-substituted β-(phenyldimethylsilyl) ketones, the oxidation of which gave the corresponding optically active β-hydroxy ketones in high yields.
