72656-59-8Relevant academic research and scientific papers
Design and application of hybrid phosphorus ligands for enantioselective Rh-Catalyzed anti-markovnikov hydroformylation of unfunctionalized 1,1-disubstituted Alkenes
You, Cai,Li, Shuailong,Li, Xiuxiu,Lan, Jialing,Yang, Yuhong,Chung, Lung Wa,Lv, Hui,Zhang, Xumu
supporting information, p. 4977 - 4981 (2018/04/24)
A series of novel hybrid phosphorus ligands were designed and applied to the Rh-catalyzed enantioselective anti-Markovnikov hydroformylation of unfunctionalized 1,1-disubstituted alkenes. By employing the new catalyst, linear aldehydes with β-chirality can be prepared with high yields and enantioselectivities under mild conditions. Furthermore, catalyst loading as low as 0.05 mol % furnished the desired product in good yield and undiminished selectivity, demonstrating the efficiency of this transformation in large-scale synthesis.
Asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated aldehydes catalyzed by a chiral diene-rhodium complex
Hayashi, Tamio,Tokunaga, Norihito,Okamoto, Kazuhiro,Shintani, Ryo
, p. 1480 - 1481 (2007/10/03)
Asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated aldehydes proceeded in the presence of a rhodium catalyst (3 mol %) coordinated with a chiral diene ligand ((R,R)-Bn-bod*) to give the corresponding β-arylaldehydes with perfect 1,4-selectivi
Design, synthesis, and application of a C2 symmetric chiral ligand for enantioselective conjugate addition of organolithium to α,β-unsaturated aldimine
Shindo, Mitsuru,Koga, Kenji,Tomioka, Kiyoshi
, p. 9351 - 9357 (2007/10/03)
A C2 symmetric chiral diether ligand, (1R,2R)-1,2-dimethoxy-1,2- diphenylethane, was designed and synthesized on the basis of the concept of an asymmetric oxygen atom. Mediated by the chiral diether, high enantioselectivities were achieved in conjugate addition of organolithiums to naphthaldehyde imine and cyclic and acyclic α,β-unsaturated aldimines. The absolute configuration of the product is predictable by the model.
1,2- vs 1,4-Addition of Nucleophilic Organometallics to Nonracemic 2-(1-Naphthyl)- and 2-Cinnamyl-1,3-oxazolidines
Pridgen, Lendon N.,Mokhallalati, Mohamed K.,Wu, Ming-Jung
, p. 1237 - 1241 (2007/10/02)
We herein report our results where the addition of organomagnesium reagents to 2-(1-naphthyl)- and 2-cinnamyl-1,3-oxazolidines occurred consistently in a 1,4-conjugate manner, while lithium, cerium and copper organometallic reagents added in a 1,2 fashion.The 1,4-conjugate addition pathway was primarely exploited by using (4R)-2-(1-naphthyl)-4-phenyl-1,3-oxazolidine (4) as a substrate to obtain, after NaBH4 reduction of the intermediate aldehyde, trans-disubstituted 1,2-dihydronaphthalenes with enantiomeric excess of 93-94percent.The amino alcohol products resulting from1,2-addition were oxidatively cleaved to afford enantiomeric enriched (R)-α-(1-naphthyl)alkylamines 6a and 6b in 99percent ee.
Asymmetric Michael Additions to α,β-Unsaturated Oxazolines. An Efficient Preparation of Chiral β,β-Disubstituted Propionaldehydes
Meyers, A. I.,Shipman, Michael
, p. 7098 - 7102 (2007/10/02)
A short stereoselective route to a variety of chiral, nonracemic α,β-unsaturated oxazolines derived from (S)-tert-leucinol is described.Addition of organolithium reagents to this chiral oxazoline occurs in a Michael fashion, giving rise to adducts with hi
Chiral Homoenolate Equivalents, II. - Asymmetric Synthesis of 3-Substituted 3-Phenylpropionaldehydes via Metallated Chiral Cinnamylamines
Ahlbrecht, Hubertus,Enders, Dieter,Santowski, Ludger,Zimmermann, Gerd
, p. 1995 - 2004 (2007/10/02)
The diastereomeric excess obtained in alkylation reactions of the chiral homoenolate equivalent 22 with prolinol ether as chiral auxiliary leading to the formation of phenylpropionaldehydes 24 depends strongly on the solvent used.The structure of the alkylating reagent on the other hand is not important.The best results (about 9:1) are obtained in tert-butyl methyl ether as solvent.Other chiral auxiliaries testet were uneffective. - Key Words: Chiral homoenolate equivalents / Alkylation / Chiral 1-aminoallyl anions / Chiral aldehydes
A NEW AND EFFECTIVE ASYMMETRIC SYNTHESIS OF 3-PHENYLALKANALS
Mukaiyama, Teruaki,Hayashi, Hiroki,Miwa, Tetsuo,Narasaka, Koichi
, p. 1637 - 1640 (2007/10/02)
Highly optically active 3-phenylalkanals were obtained by the reaction of alkyl halides and a chiral homoenolate equivalent derived from the cinnamyl ether 3 and potassium diisopropylamide, followed by acidic hydrolysis.
CHIRAL HOMOENOLATE EQUIVALENTS. I. ASYMMETRIC SYNTHESIS OF β-SUBSTITUTED ALDEHIDES VIA METALATED CHIRAL ALLYLAMINES
Ahlbrecht, Hubertus,Bonnet, Gerhard,Enders, Dieter,Zimmermann, Gerd
, p. 3175 - 3178 (2007/10/02)
Metalated chiral allylamines of type 2 (M = Li, K) are used as chiral homoenolate equivalents and allow after alkylation and acidic hydrolysis asymmetric C-C bond formations to β-substituted aldehydes in enantiomeric excesses up to 67percent.
