Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Pyrazolylborate-zinc alkoxide complexes. 2. Solvolytic chemistry.

Horst Brombacher1, Heinrich Vahrenkamp

  • 1Institut für Anorganische und Analytische Chemie der Universität Freiburg, Albertstr. 21, D-79104 Freiburg, Germany.

Inorganic Chemistry
|September 14, 2004
PubMed
Summary

Zinc methoxide complexes show selective reactivity, cleaving pyrophosphates and thiolates but not esters or lactones. Cleavage depends on leaving group ability and zinc-substrate bond strength, not just methoxide reactivity.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Why does nature use zinc--a personal view.

Dalton transactions (Cambridge, England : 2003)·2007
Same author

Modeling zinc enzyme inhibition with functional thiolate ligands.

Inorganic chemistry·2006
Same author

Zn-OH2 and Zn-OH complexes with hydroborate-derived tripod ligands: a comprehensive study.

Inorganic chemistry·2006
Same author

Thiolate alkylation in tripod zinc complexes: a comparative kinetic study.

Inorganic chemistry·2006
Same author

Tris(thioimidazolyl)borate-zinc-thiolate complexes for the modeling of biological thiolate alkylations.

Inorganic chemistry·2005
Same author

Reactions of pyrazolylborate-zinc-hydroxide complexes related to beta-lactamase activity.

Inorganic chemistry·2005

Area of Science:

  • Organometallic chemistry
  • Coordination chemistry
  • Reaction mechanisms

Background:

  • Hydrolytic cleavage reactions are fundamental in chemistry.
  • Zinc complexes are known catalysts for various transformations.
  • Understanding the reactivity of zinc alkoxides provides insights into bond activation.

Purpose of the Study:

  • To investigate the reactivity of specific zinc methoxide complexes (TpPh,MeZn-OMe and TpCum,MeZn-OMe).
  • To compare their reactivity with known zinc hydroxide complexes (Tp*Zn-OH).
  • To elucidate the factors governing the cleavage of different chemical linkages by these zinc complexes.

Main Methods:

  • Synthesis and characterization of zinc methoxide complexes.
  • Reactivity studies with various substrates including esters, phosphoesters, lactones, lactams, pyrophosphates, pyrocarbonates, and sulfur-containing compounds.

Related Experiment Videos

  • Analysis of reaction products to determine cleavage sites and efficiency.

    • Main Results:

    • Zinc methoxides did not cleave nonactivated esters, phosphoesters, lactones, or lactams.
    • Efficient cleavage of the P-O-P linkage in tetraalkylpyrophosphates was observed.
    • Cleavage of the C-O-C linkage in dialkyl pyrocarbonates was not observed.
    • Transesterification occurred for activated esters and phosphoesters (p-nitrophenolates).
    • Facile cleavage of thiolate functions in dithioesters, thiolactones, and trithiocarbonates was the most prominent reaction.

    Conclusions:

    • The reactivity of zinc methoxides is substrate-dependent, with a preference for P-O-P and thiolate linkages.
    • While methoxide leaving group ability is important, the strength of the formed zinc-substrate bond is the critical factor determining cleavage.
    • These findings contribute to understanding the selectivity and mechanisms of zinc-mediated bond activation reactions.