Novel Telluro-ketones By Mrs Naziah Jaufeerally Myself Mrs Naziah - - PowerPoint PPT Presentation

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Novel Telluro-ketones By Mrs Naziah Jaufeerally Myself Mrs Naziah - - PowerPoint PPT Presentation

Oct 10, 2022 253 likes •670 views

Structures, Energetics and Stabilities 1 of Novel Telluro-ketones By Mrs Naziah Jaufeerally Myself Mrs Naziah Jaufeerally Prof Ponnadurai Ramasami PhD scholar 2 Target Molecules Telluroformaldehyde/ Silanetellone/ Germanetellone 3 Why

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Structures, Energetics and Stabilities

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Novel Telluro-ketones

By Mrs Naziah Jaufeerally

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Myself

Mrs Naziah Jaufeerally PhD scholar

Prof Ponnadurai Ramasami

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Target Molecules

Telluroformaldehyde/ Silanetellone/ Germanetellone

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Why the study of Heavy Congeners of H2C=O ?

F2C=O Cl2C=O

X2C=O (X=F and Cl) major products

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photolysis

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halomethanes in presence of oxygen

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mainly to check the reliability

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quantum mechanical computing methods C=O group- important organic moiety in industry and biology

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– Important intermediates in sulfur and selenium containing molecules – Composition of nucleic acid and ribose sugars of some active metabolites – Useful anti-tumour drugs

Thio- and Seleno- analogues

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But the literature of telluro-ketones is scarce. Despite Telluroformaldehyde complexes were first synthesized in 1983.

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Telluroformaldehyde

C

Te H H

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However, nowadays there is a quest for tellurium containing compounds or tellurocarbonyl compounds.

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Importance of Telluro-ketones

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Importance of Telluro-ketones

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Monomeric H2Si=S has reached the STARS!

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Why Limited literature for Telluro-ketones?

Theoretical exploration has been scarce due to:

  • Lack of well-tested basis sets for Te atom
  • Limited computing resources
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Why Limited literature for Telluro-ketones?

The lack of experimental studies is often ascribed to:

  • The semipolar nature of the A=E bond

(A=C, Si and Ge; E=O, S, Se and Te)

  • High tendency for the A=E to open up

and undergo intermolecular reactions

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Stable Monomeric Germanone

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Telluro- ketones

Molecular geometries

Ionization Potentials Electron Affinities Singlet- Triplet Splittings HOMO- LUMO

gaps

Kinetics Isomeriz- ations

Objectives of this research work

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Our Findings

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Our Findings

The kinetic and thermodynamic stabilities of the telluro-ketones were always questioned by reviewers.

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Back to literature… How others have stabilized some of the known heavy ketones? Has any stable telluro-ketone been synthesized and isolated so far?

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Conclusions from literature… Heavy ketones and telluro-ketones synthesized and isolated so far are based on the kinetic stabilization of the A=E bond by the use of bulky rigid protecting groups.

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Does this means that the simple, unprotected telluro-ketones are unstable compared to those kinetically protected ones?

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Our Response to the Queries

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Our Response to the Queries

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Our Response to the Queries

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Our Response to the Queries

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Our Response to the Queries

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Our Response to the Queries

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Further Objectives

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Existence of Telluro-ketones is Not a Myth But a Reality!

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In view of this, we are currently working

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the following manuscript

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Stabilization of the C=Te, Si=Te and Ge=Te double bonds

With the help of rigid and bulky protecting groups Modeled from the 1st synthetic success of germanetellone reported in JACS

Further Studies

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Stabilization of the C=Te, Si=Te and Ge=Te double bonds

With the help of rigid and bulky protecting groups Modeled from the 1st synthetic success of germanone reported in Nature Chemistry

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Stabilization of the C=Te, Si=Te and Ge=Te double bonds

With the help of Lewis donor-acceptor ligands

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Conclusions

Since

state-of-the-art computations have been carried out, findings of this work can serve as a good reference and assist experimentalists to

 synthesize, characterize and further explore the properties of these novel

telluro-ketones

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Acknowledgements

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I gratefully acknowledge:

 the organising committee of 17th ECSOC  Our collaborators: Prof HF Schaefer, Prof G Frenking and

Dr H Abdallah

 the University of Mauritius  the computing facility of Gridchem  the Tertiary Education Commision (TEC)

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Thank You

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