85922-31-2Relevant academic research and scientific papers
A Versatile and practical solvating agent for enantioselective recognition and NMR analysis of protected amines
Iwaniuk, Daniel P.,Wolf, Christian
supporting information; experimental part, p. 6724 - 6727 (2010/12/19)
The 3,5-dinitrobenzoyl-derived 1-naphthylethyl amide 3 is an attractive CSA for NMR analysis of protected amines. It is readily prepared in a single step and combines practical resolution of diastereomeric complexes due to signal sharpness and effective signal separation. Crystallographic analysis shows that 3 forms a chiral cleft that can selectively bind one enantiomer of a substrate through hydrogen bonding, π-π stacking, and CH/π interactions. The enantioselective complex formation causes strong upfield shifts in the 1H NMR spectrum even in the presence of only 5 mol % of 3.
Remarkable effects of chirality on deslipping reactions of diastereomeric rotaxanes and relevant mechanism involving pre-equilibrium
Hirose, Keiji,Nakamura, Yamato,Tobe, Yoshito
supporting information; experimental part, p. 145 - 147 (2009/08/07)
The first clear differentiation on deslipping rates affected by the difference in the diastereomeric stereocenters of rotaxanes up to 8.4 times and unexpectedly large steric kinetic isotope effect on the deslipping reaction.
Stereoselective alkylations of chiral nitro imine and nitro hydrazone dianions. Synthesis of enantiomerically enriched 3-substituted 1-nitrocyclohexenes
Denmark, Scott E.,Ares, Jeffrey J.
supporting information; experimental part, p. 9647 - 9656 (2009/04/11)
(Chemical Equation Presented) Dianions of chiral nitro imines (generated by a combination of LDA and s-BuLi) underwent diastereoselective alkylation with methyl, butyl, isopropyl, allyl, and methallyl iodides. In contrast to the behavior of simple metalloenamines, the most selective auxiliary contained no coordinating groups but did possess a large steric difference between the two substituents. The yield and selectivity of the alkylations were improved by the addition of HMPA or DMPU. The use of (S)-1-naphthylethylamine as the auxiliary afforded the R absolute configuration of the alkylation products. This stereochemical outcome could be rationalized by simple steric approach controlled alkylation in a conformationally fixed, internally coordinated dianion. A SAMP nitro hydrazone gave poorer yields and selectivities.
Chiral NMR shift reagents: Mixtures of lanthanide tris (β-diketonates) with chiral carboxylate anions
Wenzel, Thomas J.,Bean, Amy C.,Dunham, Sarah L.
, p. 395 - 402 (2007/10/03)
Chiral carboxylic acids such as N-(R)-1-(1-naphthyl)ethylaminocarbonyl-L-tert-leucine, N-(R)-1-(1-naphthyl)ethylaminocarbonyl-L-valine and N-(3,5-dinitrobenzoyl)-L-leucine are solubilized in chloroform by the addition of triethylamine. The resulting ion p
A CONVENIENT FAMILY OF CHIRAL SHIFT REAGENTS FOR MEASUREMENT OF ENANTIOMERIC EXCESSES OF SULFOXIDES
Deshmukh, M.,Dunnach, E.,Juge, S.,Kagan, H. B.
, p. 3467 - 3470 (2007/10/02)
(R)(-)-N-(3,5-dinitrobenzoyl)-α-phenylethylamine is a good chiral shift reagent for sulfoxides such as Ar-(SO)-CH3 (Ar=substituted phenyl, naphtyl) or R-(SO)-CH3 (R=t-Bu,Cyclohexyl,n-Octyl). 1-Naphthyl propyl sulfoxide was also successfully resolved.The s
