Stepwise Chemical Reduction of [4]Cyclo[4]helicenylene: Stereo Transformation and Site-Selective Metal Complexation DOI Creative Commons
Zheng Zhou, Yang Yong,

Jianwei Liang

et al.

Precision Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

A highly strained macrocycle comprising four [4]helicene panels, [4]cyclo[4]helicenylene ([4]CH, 1), was synthesized through a one-pot macrocyclization and chemically reduced by alkali metals (Na K), revealing four-electron reduction process. The resulting di-, tri-, tetraanions of compound 1 were isolated crystallographically characterized X-ray diffraction. Owing to the axially chiral bi[4]helicenyl fragments, reversible stereo transformation between (S,R,S,R)- (S,S,R,R)-configurations disclosed upon two-electron uptake, which rationally understood theoretical calculations. (S,S,R,R)-configuration 2- further stabilized in triply tetra-reduced states, where structural deformation led charges metal complexation observed. This study proposed an approach alter configuration cycloarylenes addition thermal treatment.

Language: Английский

Thermally-induced atropisomerism promotes metal-organic cage construction DOI Creative Commons
Jiaqi Liang, Shuai Lu, Yang Yang

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Dec. 9, 2023

Molecular folding regulation with environmental stimuli is critical in living and artificial molecular machine systems. Herein, we described a macrocycle, cyclo[4] (1,3-(4,6-dimethyl)benzene)[4](1,3-(4,6-dimethyl)benzene)(4-pyridine). Under 298 K, it has three stable stiff atropisomers names as 1 (Cs symmetry), 2 3 (C4v symmetry). At 393 can reversibly transform into 2, but at 473 irrevocably 3. 338 (PhCN)2PdCl2 complex to produce the metal-organic cage 4. Only K does combination of or create gel-like structure. Heating both gels transforms them In addition offering thermally accelerated method for modifying self-assembled systems using macrocyclic building blocks, this study also potential develop nanoscale transformation material thermal response.

Language: Английский

Citations

7
Asymmetric Cycloaddition Reactions of Aryne Intermediates with a Chiral Carbon–Carbon Axis: Syntheses of Axially Chiral Biaryl Compounds DOI
Tomoyuki Yoshimura,

Kenichi Onda,

Jun‐ichi Matsuo

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(49), P. 8952 - 8956

Published: Dec. 6, 2023

An asymmetric synthesis via an axially chiral arylaryne intermediate was developed. A cycloaddition reaction with various arynophiles used to obtain biaryl compounds while preserving the enantiomeric excess (ee) of a precursor even though proceeds through intermediate, whose ee decreases on time-dependent basis. High transfer from product observed not only at low temperature (−78 °C) but also room temperature.

Language: Английский

Citations

1
Controlled interconversion of macrocyclic atropisomers via defined intermediates DOI Creative Commons
Xin Sun,

Jin-Ku Bai,

Yu‐Dong Yang

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 2, 2024

Macrocyclic conformations play a crucial role in regulating their properties. Our understanding of the determinants to control macrocyclic conformation interconversion is still its infancy. Here we present macrocycle, octamethyl cyclo[4](1,3-(4,6)-dimethylbenzene)[4]((4,6-benzene)(1,3-dicarboxylate) (OC-4), that can exist at 298 K as two stable atropisomers with C2v and C4v symmetry denoted C2v-OC-4 C4v-OC-4, respectively. Heating induces efficient stepwise conversion C2v- C4v-OC-4 via Cs-symmetric intermediate (Cs-OC-4). It differs from typical transition state-mediated processes simple C–C single bond rotations. Hydrolysis further esterification countercation dependence promote generation Cs-OC-4 C4v-OC-4. In contrast C2v-OC-4, bind linear guests form pseudo-rotaxans, or C60 C70 efficiently. The study highlights differences recognition behavior result conformational interconversion, well providing insights into basic parameters govern coupled molecular three-dimensional macrocycles determine chemical properties factors influence between forms are poorly understood. authors describe macrocycle existing mechanism behind thermally-induced them.

Language: Английский

Citations

0
Stepwise Chemical Reduction of [4]Cyclo[4]helicenylene: Stereo Transformation and Site-Selective Metal Complexation DOI Creative Commons
Zheng Zhou, Yang Yong,

Jianwei Liang

et al.

Precision Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

A highly strained macrocycle comprising four [4]helicene panels, [4]cyclo[4]helicenylene ([4]CH, 1), was synthesized through a one-pot macrocyclization and chemically reduced by alkali metals (Na K), revealing four-electron reduction process. The resulting di-, tri-, tetraanions of compound 1 were isolated crystallographically characterized X-ray diffraction. Owing to the axially chiral bi[4]helicenyl fragments, reversible stereo transformation between (S,R,S,R)- (S,S,R,R)-configurations disclosed upon two-electron uptake, which rationally understood theoretical calculations. (S,S,R,R)-configuration 2- further stabilized in triply tetra-reduced states, where structural deformation led charges metal complexation observed. This study proposed an approach alter configuration cycloarylenes addition thermal treatment.

Language: Английский

Citations

0