6995-48-8Relevant academic research and scientific papers
Palladium-Catalyzed Enantioselective Redox-Relay Heck Arylation of 1,1-Disubstituted Homoallylic Alcohols
Chen, Zhi-Min,Hilton, Margaret J.,Sigman, Matthew S.
, p. 11461 - 11464 (2016/10/06)
An enantioselective redox-relay oxidative Heck arylation of 1,1-disubstituted alkenes to construct β-stereocenters was developed using a new pyridyl-oxazoline ligand. Various 1,2-diaryl carbonyl compounds were readily obtained in moderate yield and good to excellent enantioselectivity. Additionally, analysis of the reaction outcomes using multidimensional correlations revealed that enantioselectivity is tied to specific electronic features of the 1,1-disubstituted alkenol and the extent of polarizability of the ligand.
Asymmetric syntheses and bio-evaluation of novel chiral esters derived from substituted tetrafluorobenzyl alcohol
Xu, Shengzhen,Li, Huangyong,Wang, Xiaohui,Chen, Changshui,Cao, Minhui,Cao, Xiufang
supporting information, p. 2734 - 2736 (2015/02/19)
A series of novel chiral esters derived from tetrafluorobenzyl alcohol were designed and prepared via asymmetric synthesis. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened their potential insecticidal activity against Plutella xylostella compared with those of fenvalerate and d-trans-phenothrin by standard method, and the respective pairs of enantiomers (3-B1-R/S, 3-C1-R/S, 3-D1-R/S) indicated significantly different activities.
Asymmetric syntheses and bio-evaluation of novel chiral esters derived from substituted tetrafluorobenzyl alcohol
Xu, Shengzhen,Li, Huangyong,Wang, Xiaohui,Chen, Changshui,Cao, Minhui,Cao, Xiufang
supporting information, p. 2734 - 2736 (2014/06/09)
A series of novel chiral esters derived from tetrafluorobenzyl alcohol were designed and prepared via asymmetric synthesis. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened their potential insecticidal activity against Plutella xylostella compared with those of fenvalerate and d-trans-phenothrin by standard method, and the respective pairs of enantiomers (3-B1-R/S, 3-C1-R/S, 3-D1-R/S) indicated significantly different activities.
Synthetic applications of the β-lithiation of β-Aryl secondary amides: Diastereoselective and enantioselective substitutions
Lutz, Gary P.,Du, Hua,Gallagher, Donald J.,Beak, Peter
, p. 4542 - 4554 (2007/10/03)
The sequence of β-lithiation and electrophilic substitution of β-aryl secondary amides is reported. The lithiations occur regioselectively at the β-position, and the resulting lithiated intermediates can be reacted with a wide range of electrophiles to give substituted products. Reactions of β-lithiated amides bearing an α-substituent provide substituted products with high diastereoselectivity. Electrophilic substitutions of β-lithiated N-methylamides in the presence of the chiral diamine (-)-sparteine provide highly enantioenriched products. The methodology is used to synthesize enantioenriched β-aryl β-substituted amides, acids, and lactones.
Regio-, Stereo-, and Enantioselectivity in the Electrophilic Reactions of 2-Amino-4-phenyl-3-butenenitriles
Chang, Chih-Jung,Fang, Jim-Min,Liao, Li-Fan
, p. 1754 - 1761 (2007/10/02)
The allylic anion generated from 2-(N-methylanilino)-4-phenyl-3-butenenitrile (1) reacted with iodomethane and 3-bromo-1-chloropropane in THF/HMPA to give γ-substituted products exclusively, predominantly in the 2Z-configuration.Substitution of the N-methylanilino group with the methyl ether of L-(-)-ephedrine resulted in the generation of chiral aminonitrile 2.Lithiated 2 reacted sluggishly in THF with allyl bromide and benzyl chloride in the absence of HMPA to give the γ-substituted products predominantly in the 2Z-configuration, with little diastereoselectivity.The aminonitrile 3 prepared from cinnamaldehyde, L-(-)-ephedrine, and KCN was lithiated with 2 equiv of LDA resulting in high facial selectivity (76 - 100 percent diastereomeric excess) in alkylations in the presence of HMPA and LiI.Lithiated 3 reacted with propionaldehyde, benzaldehyde, and p-bromobenzaldehyde at -78 deg C to give the γ-addition products, predominantly in the 4R-configuration (64 -78 percent de).The stereochemistry of the isomers of each product was determined by chemical correlation and spectral methods including analyses of the CD spectra and X-ray diffraction.A bicyclic transition state C wherein lithium is chelated by both amino and alkoxy groups is proposed to interpret the observed stereoselectivity.
Asymmetric Michael additions of Grignard reagents to cinnamamides deriving from N-alkyl (R)-(-)-2-aminobutan-1-ol
Touet,Baudouin,Brown
, p. 587 - 590 (2007/10/02)
Reaction of cinnamoyl chloride with various N-alkyl derivatives of (R)-(-)-2-aminobutan-1-ol (a readily available reagent) afforded the corresponding cinnamamides. Michael additions of Grignard reagents to the latter, followed by acidic hydrolysis, yielde
