Polyhalogenated Cyclopentadienes in [4+2] Cycloadditions: Preparative Aspects

Eibler, E.; Burgemeister, Thomas; Höcht, Peter; Prantl, B.; Rossmaier, H.; Schuhbauer, H. M.; Wiest, H.; Sauer, Jürgen

doi:10.1002/jlac.199719971208

Cited by 9 publications

(13 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sauer et al studied tetrachlorocyclopentadienes as reactants in Diels–Alder reactions, , and Houk et al after extensive computational and experimental studies ,− introduced them to bioorthogonal chemistry . Such highly substituted cyclopentadienes are stable in solution in contrast to most cyclopentadienes that undergo dimerization. ,,, Furthermore, the geminal halogen substituents at the C-5 carbon increase reactivity by hyperconjugation.…”

Section: Inverse-electron Demand Diels-alder Cycloaddition Reactionsmentioning

confidence: 99%

Mechanisms and Substituent Effects of Metal-Free Bioorthogonal Reactions

Deb

Franzini

2021

Chem. Rev.

View full text Add to dashboard Cite

Reactions that occur under physiological conditions find diverse uses in the chemical and biological sciences. However, the limitations that biological systems place on chemical reactions restrict the number of such bioorthogonal reactions. A profound understanding of the mechanistic principles and structure−reactivity trends of these transformations is therefore critical to access new and improved versions of bioorthogonal chemistry. The present article reviews the mechanisms and substituent effects of some of the principal metal-free bioorthogonal reactions based on inverse-electron demand Diels−Alder reactions, 1,3-dipolar cycloadditions, and the Staudinger reaction. Mechanisms of modified versions that link these reactions to a dissociative step are further discussed. The presented summary is anticipated to aid the advancement of bioorthogonal chemistry. CONTENTSReview pubs.acs.org/CR

show abstract

Section: Inverse-electron Demand Diels-alder Cycloaddition Reactionsmentioning

confidence: 99%

Mechanisms and Substituent Effects of Metal-Free Bioorthogonal Reactions

Deb

Franzini

2021

Chem. Rev.

View full text Add to dashboard Cite

show abstract

“…14,15 Sauer’s detailed reports on the synthesis and reactivities of substituted cyclopentadienes, however, have gone relatively unrecognized. 39,40 The highly reactive, self-orthogonal, and ambiphilic properties of the tetrachlorocyclopentadiene ketal (TCK) shown in Scheme 3 and described by Sauer attracted our attention to it as a potential bioorthogonal diene. 39,40 Ambiphilic molecules can react as electrophiles or nucleophiles, depending on the reaction partner.…”

Section: Introductionmentioning

confidence: 99%

“…Cyclopentadiene reacts as both a diene and a dienophile in the Diels–Alder reaction and readily dimerizes at room temperature . Highly substituted cyclopentadienes, such as hexachlorocyclopentadiene, are reactive as dienes but do not readily dimerize at room temperature. , Dienes with this lack of self-reactivity are referred to as “self-orthogonal”. Substituents at the 1,2 and 3,4 positions of cyclopentadiene sterically impede dimerization by clashing with the substituents at the 5-position of the cyclopentadiene.…”

Section: Introductionmentioning

confidence: 99%

“…Sauer’s pioneering studies on the synthesis and reactivities of 1,2,4,5-tetrazines with many dienophiles have provided inspiration for the design of a variety of reactions in bioorthogonal chemistry. , Sauer’s detailed reports on the synthesis and reactivities of substituted cyclopentadienes, however, have gone relatively unrecognized. , The highly reactive, self-orthogonal, and ambiphilic properties of the tetrachlorocyclopentadiene ketal (TCK) shown in Scheme and described by Sauer attracted our attention to it as a potential bioorthogonal diene. , Ambiphilic molecules can react as electrophiles or nucleophiles, depending on the reaction partner. TCK, being ambiphilic, is able to react with both electron-deficient dienophiles, such as maleic anhydride, and electron-rich dienophiles, such as (1 Z ,5 Z )-cycloocta-1,5-diene .…”

Section: Introductionmentioning

confidence: 99%

“…39,40 The highly reactive, self-orthogonal, and ambiphilic properties of the tetrachlorocyclopentadiene ketal (TCK) shown in Scheme 3 and described by Sauer attracted our attention to it as a potential bioorthogonal diene. 39,40 Ambiphilic molecules can react as electrophiles or nucleophiles, depending on the reaction partner. TCK, being ambiphilic, is able to react with both electron-deficient dienophiles, such as maleic anhydride, and electron-rich dienophiles, such as (1Z,5Z)-cycloocta-1,5-diene.…”

Section: ■ Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Readily Accessible Ambiphilic Cyclopentadienes for Bioorthogonal Labeling

et al. 2018

View full text Add to dashboard Cite

A new class of bioorthogonal reagents based on the cyclopentadiene scaffold is described. The diene 6,7,8,9-tetrachloro-1,4-dioxospiro[4,4]nona-6,8-diene (a tetrachlorocyclopentadiene ketal, TCK) is ambiphilic and self-orthogonal with remarkable stability. The diene reacts rapidly with a trans-cyclooctene and an endo-bicyclononyne, but slowly with dibenzoazacyclooctyne (DIBAC), allowing for tandem labeling studies with mutually orthogonal azides that react rapidly with DIBAC. TCK analogues are synthesized in three steps from inexpensive, commercially available starting materials.

show abstract