Synthesis and transport studies of a new class of cage-annulated chiral macrocycles

Govender, Thavendran; Hariprakasha, H. K.; Kruger, Hendrik G.; Marchand, Alan P.

doi:10.1016/s0957-4166(03)00272-6

Cited by 33 publications

(28 citation statements)

References 17 publications

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“…These reactions used the high dilution technique. [29][30][31] This method involves dropping the two reactants into a reaction vessel at the same time and speed from two different dropping funnels into a large volume of solvent. Due to the slow (ca.…”

Section: Scheme 1 Preparation Of New Methyl-[(ss)-9] and Isobutyl-smentioning

confidence: 99%

Synthesis and determination of pKa values of new enantiopure pyridino- and piperidino-18-crown-6 ethers

Kupai

Kisszékelyi

Rojik

et al. 2016

Arkivoc

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This paper reports the preparation of eight new enantiopure amide type crown ethers and their optically active precursors. Chiral diamines were transformed to amide type pyridino-crown ethers reacting them with pyridine dicarbonyl dichlorides by high dilution technique. Two of the new pyridino-crown ethers were reduced to their piperidino analogues. A preliminary study for the potential application of nanofiltration in the purification and recovery of crown ethers is presented. According to the pK a measurements these eight new macrocycles are potential organocatalysts (for instance in Michael addition reactions) thanks to their acidic and basic moieties and chiral skeletons, respectively.

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Section: Scheme 1 Preparation Of New Methyl-[(ss)-9] and Isobutyl-smentioning

confidence: 99%

Synthesis and determination of pKa values of new enantiopure pyridino- and piperidino-18-crown-6 ethers

Kupai

Kisszékelyi

Rojik

et al. 2016

Arkivoc

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“…[10] Ozonolysis of the diol 10 followed by an oxidative workup yielded the PCU diol dicarboxylic acid 11. Compound 11 is reacted with ammonium chloride using coupling reagents hydroxybenzotriazole (HOBt), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-methylmorpholine (NMM) to obtain compound 1 (Scheme 1).…”

Section: Introductionmentioning

confidence: 99%

“…[10,21] Compound 12 was converted to its corresponding diacid chloride [10] and reacted with ammoniasaturated chloroform at 0…”

Section: Introductionmentioning

confidence: 99%

Synthesis and NMR assignment of pentacycloundecane precursors of potential pharmaceutical agents

Onajole

Makatini

Gasqui

et al. 2010

Magnetic Reson in Chemistry

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The synthesis and complete NMR elucidation of eight novel pentacycloundecane (PCU) derivatives are reported. These compounds are precursors in the synthesis of PCU-based anti-tuberculosis (TB) agents and potential human immunodeficiency virus (HIV) protease inhibitors. Two-dimensional (2D) NMR techniques were used to assign the NMR spectra for these compounds. Substitution of the cage molecule at (C-8/11) further complicates the assignment, since some of the substituted alkyl chain groups overlap with the cage proton signals. The side chain heteroatoms also introduce a rare through-space deshielding effect to some of the carbon atoms of the cage skeleton. Ring strain in the rigid cage skeleton appears to induce drastic electronic changes in some parts of the cage framework. This observation is more dramatic for the C-4 methylene group of the cage diols and the cage ethers.

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“…[15,16] This diene 7 is an intermediate in the synthesis of all the derivatives 1-5 being investigated. Ozonolysis of 7 followed by an oxidative workup using formic acid and hydrogen peroxide afforded the PCU diacid 8.…”

Section: Introductionmentioning

confidence: 99%

“…Ozonolysis of 7 followed by an oxidative workup using formic acid and hydrogen peroxide afforded the PCU diacid 8. [15] To avoid competing reactions due to the free hydroxyl group on the amino alcohol, it was decided to protect the alcohol by using tert-butyldimethylsilyl (TBDMSi) chloride to give (S) tert-butyldimethylsilyl 2-amino-3-phenylpronoate 9. [17] This protecting group is known to be hydroxyl group selective in the presence of a primary amine.…”

Section: Introductionmentioning

confidence: 99%

NMR elucidation of a novel (S)‐pentacyclo‐undecane bis‐(4‐phenyloxazoline) ligand and related derivatives

Boyle

Govender

Kruger

et al. 2008

Magnetic Reson in Chemistry

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The NMR elucidation of a novel ligand (S)-pentacyclo-undecane bis-(4-phenyloxazoline) and related pentacyclo-undecane (PCU) derivatives is reported. Two-dimensional NMR proved to be a powerful technique in overcoming the difficulties associated with the elucidation of these compounds when only one-dimensional NMR data is utilized. A chiral substituent was introduced to both 'arms' of the PCU skeleton to produce derivatives 1-3. These derivatives display C(1) symmetry with all thecage atoms being nonequivalent. Owing to overlapping of peaks in the (1)H spectra, identification of these diastereomeric protons was very difficult. The (13)C spectra gave rise to clear splitting of the nonequivalent carbons. This is unusual compared to similar PCU derivatives with chiral substituents as splitting of all the diastereomeric cage carbons has not yet been reported. Nuclear Overhauser enhancement spectroscopy (NOESY) correlations of derivatives 1-3 confirm the different conformations of the molecule in which the side 'arms' occupy different orientations with respect to cage moiety.

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Synthesis and transport studies of a new class of cage-annulated chiral macrocycles

Cited by 33 publications

References 17 publications

Synthesis and determination of pKa values of new enantiopure pyridino- and piperidino-18-crown-6 ethers

Synthesis and determination of pKa values of new enantiopure pyridino- and piperidino-18-crown-6 ethers

Synthesis and NMR assignment of pentacycloundecane precursors of potential pharmaceutical agents

NMR elucidation of a novel (S)‐pentacyclo‐undecane bis‐(4‐phenyloxazoline) ligand and related derivatives

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