Conversion%20of%20osmasilabenzyne%20into%20silylene%20complexes

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Conversion of osmasilabenzyne into silylene
complexes

• Ying Huang(??)
• Adviser Jun Zhu(??)

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• Outline
• 1. Backgroud
• 2. Conversion of osmasilabenzyne into silylene
  complexes
• 3. Conversion of the carbyne complex into the
  corresponding benzyne complex.
• 4. Conclusion and next to do

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Backgroud
Aromaticity
Conjugation energy 44.35kcal/mol
Tingbin Wen, Guochen Jia. Angew. Chem. Int. Ed.
2001, 40,1951
Guochen Jia, Zhenyang Lin. Organometallics,
2003,22,3898.
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Electrophilic Substitution
The electrophilic Substitution usually occur at
the C2 and C4 positions of the metallacycle
Zhenyang Lin, Guochen Jia. J. Am. Chem. Soc.
2011, 133, 18350
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The effect of substituents
The calculated relative free energies and
electronic energies (in parentheses) are given in
kcal/mol.
Zhenyang Lin, Guochen Jia. Angew. Chem. Int. Ed.
2011, 50, 7295
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DFT Package Gaussian 03 Method B3LYP basis
sets 6-31G LanL2DZ (Os (f)
0.886) (Si(f)
0.262) (P (f)
0.340))
The calculated relative free energies and
electronic energies (in parentheses) are given in
kcal/mol.
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Occupied ?-molecular orbitals of osmasilabenzyne
HOMO-6
HOMO
HOMO-4
HOMO-9
HOMO-10
HOMO-12
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Substituents effect
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The Effect Of Substituents At The Ring
R PPh3
RNO2
RPH3
R PMe3
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The effect of substituents at the ring
RMe
Rn-pentyl
ROMe
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The Highest occupied molecular orbitals of
osmasilabenzyne complexes
stable
NO2
OMe
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The Highest occupied molecular orbitals of
osmasilabenzyne complexes
NO2
stable
OMe
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Substituents effect
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The Effect Of Substituents At The Ring
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Reason
C1
C1
-0.196
-0.184
The charge of C1
The silyl group on the carbon adjacent to the
carbyne carbon can prevent the protonation back
to the corresponding osmabenzene through its
polarization effect
Shengyong Yang, Journal of Organometallic
Chemistry 2002,658 ,9.
The charge of Si 0.240
0.158
0.118
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The Highest occupied molecular orbitals of
osmasilabenzyne complexes
Me
t-Bu
TMS
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The Effect Of Substituents At The Ring
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The Effect Of Substituents At The Ring
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The Lowest unoccupied molecular orbitals of
osmasilabenzyne complexes
stable
NO2
OMe
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Substituents effect
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TS
LUMO
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Detail 1
R PPh3
RNO2
RPH3
R PMe3
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Detail 1
can PH3 replace PMe3 ?
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Detail 1
R
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Detail 2
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The Effect Of Substituents At The Ring
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The Effect Of Substituents At The Ring
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conclusion

1. Theoretical calculations at the B3LYP level of
   density functional theory have been carried out
   to study the migratory insertion reactions from
   osmasilabenzyne complexes to silylene complexes.
2. The effect of substituents at the ring on the
   stabilities has also been explored, we found that
   the effect of substituents in the six-membered
   ring play important roles in determining the
   relative stabilities.
3. Furthermore, the possible path from some
   silylidyne complexes to the silylene complexes
   have found.

Next to do

1. Compute the ELF(electron localization function)
   to find the reason why the osmasilabenzyne
   complex is less stable than the osmabenzyne
   complex.
2. Explore the answers about these problems which
   have mentioned just now.
3. Realize the Conversion of silylene complexes into
   osmasilabenzyne.

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Thanks for your attention