Post on 14-Dec-2015
Isomerization from Silacyclopentadienyl Complexes to Rhodasilabenzenes, Possible or Not?
Ying huang
Si[Rh']
Si
Possible?
[Rh]
R
R
Contxet
Background
My work
Result Summary and next work
1. What’s metallabenzene complexes?
.
[M] = MLn, MLn-1X or MLn-2X2
2.History
In 1979 ,Thorn and Hoffmann predicted the three classes of stable metallabenzenes
.
D.L. Thorn, R. Hoffmann, Nouv. J. Chim,1979, 3, 39
Mn
L
L
LRh
L
L
Cl
Cl
Rh
L
L
LL
L is a neutral 2e- donor ligand
Metallabenzene
In 1982
Since then Various metallaaromatics have been reported.
the first metallabenzene
W.R. Roper, J. Chem. Soc. Chem.Commun. 1982, 811
M.M. Haley,Organometallics,2003, 22, 3279; M.M. Haley, Chem. Eur. J, 2005, 11,1191
Iridabenzene
3 1
Rhodabenzene
No rhodabenzene has yet been isolated. only rhodabenzvalene was isolated at -30 in 2002.℃
M. M. Haley, Organometallics ,2002,21,4320
48%
Reasons DFT calculations
(diffuse functions for use with the SDD and SDB-cc-pVDZ basis set-RECP combinations are presented for the transition metals.)
M. E.van der Boom,J.M. L. Martin, J. Am. Chem. Soc. 2004, 126, 11699
Rh
H3P PH3
RhH3P
PH3
H3P
20.5 kcalmol-1
-56.8 kcalmol-1
TS
SilabenzeneAromaticity HF(B3LYP/6-311G**)
Si- C :1.771 Å
ASE( aromatic stabilization energy) :70–85% (6-31G*) of that of benzene.
Apeloig, Y., Karni, M. ,Wiley: NewYork,1998, 2, Chapter 1.
But simple neutral silaaromatic compounds are known to be highly reactive.
Si
Free energy surface (kcal/mol) in the reaction of silabenzene with acetylene. ( B3LYP/6-31G(d))
N.Tokitoh,J. Chin. Chem. Soc,2008,55, 3
Reason
synthesis
No silabenzene stable at ambient temperature has ever been reported until 1999.
2,4,6-tris[bis(trimethylsilyl)methyl]phenyl
N . Tokitoh ,Pure Appl. Chem, 1999,71, 495.
Molecular structure of Tbt-substituted silabenzene
bond lengths (Å): Si-C=1.765(1.770)C-C =1.391(1.399;1.381;1.394)
N.Tokiton,Acc. Chem. Res. 2004, 37, 86
X-rayRaman
Schematic drawings of the vibrational modes for the strongest in-plane vibrations of benzene and silabenzene
N.Tokitoh,Organometallics , 2005 , 24 , 6141
Half-Sandwich complexes containing Si
A. Sekiguchi ,J. Am. Chem. Soc,2009, 131, 9902
Rhodium Half-Sandwich
47%
The first group 9 metal complex with the heavy cyclopentadienyl ligand and the first heavy cyclopentadienyl complex of half-sandwich type.
bond lengths (Å): Si1-Si2 =2.2294(8),Si2-Si3 = 2.2807(8), Si1-C2 =1.871(2), Si3-C1 = 1.857(2), C1-C2=1.413(3), Si1-Si4 =2.3864(8), Si2-Si5 =2.3821(8), Si3-Si6 =2.4001(8), Rh1-Si1 =2.5231(6), Rh1-Si2 =2.6845(6), Rh1-Si3 =2.4806(6), Rh1-C1 =2.371(2), Rh1-C2 = 2.323(2), Rh1-C34 =1.900(2), Rh1-C35 =1.873(2), C34-O1 =1.141(3), C35-O2 =1.147(3).
Zhenyang Lin , Guochen Jia,Dalton Trans., 2011, 40, 11315
DFTPackage : Gaussian 03Method: B3LYPbasis sets : 6-31G LanL2DZ (Re(z(f) = 0.869))
[Re']Possible?
[Re]
R
R
energies for the rearrangement reactions of rhenabenzenes. The relative electronic energies and Gibbs free energies at 298 K (in parentheses) are given in kcal mol -1.
Effect of 2OMe substituent on reaction energies for the rearrangement reactions of rhenabenzene.
possible
Energy profiles calculated for the formation of the rearrangement of 1 to 2. The relative electronic energies and Gibbs free energies at 298 K (in parentheses) are given in kcal mol-1.
TS
My work
bond lengths (Å): Si3-Si4 =2.21321 (2.2807),Si2-Si3 =2.21328(2.2294),Si4-C10=1.87771(1.857),Si2-C11=1.87793 (1.871), C10-C11=1.39592(1.413), Si4-Rh=2.51113(2.4806), Si2-Rh=2.51036(2.5231),Si3-Rh= 2.77879 (2.6845), C11-Rh=2.51842(2.323), C10-Rh=2.51852(2.371)
H. Yasuda, V. Ya. Lee, A. Sekiguchi ,J. Am. Chem. Soc, 2009, 131, 9902.
DFTPackage : Gaussian 03Method: m05basis sets : 6-31G * LanL2DZ (Rh (z(f) = 1.350) Si(z(f)= 0.262) P (z(f) =0.340))
The Gibbs free energies and the relative electronic energies (in parentheses) are given in kcal/mol
SiSi
Si
RhH3Si
H3Si
H3Si
CH3
CH3
OC CO
0.0(0.0)
Si
Rh Si
Si
H3Si
SiH3
SiH3
H3CCH3
CO
OC
57.10(58.34)
SiSi
Si
Rh
OC CO
Si
Rh Si
SiCO
OC
52.2(50.1)
Si
Rh
OC CO
Si
Rh
CO
OC34.0(35.8)
0.0(0.0)
Si
Rh
CO
OC
OC31.24(22.03)
0.0(0.0)
-CO
Si
[Rh] + SiH3CH3 + 3CH3CH3 + 2CH2CH2 CH3[Rh] SiH2
+ CH3SiH2CH3 + 4CH3CHCH2
[Rh]=Rh(CO)3
Si
Rh
CO
OC
OC
13.7(10.1)Kcal/mol
B3LYP
Guochen Jia, Zhenyang Lin, Organometallics 2003, 22, 3898
[Os] = Os(PH3)2(CO)I
Conjugation energies:46.66 kcal/mol
Conjugation energies:43.52 kcal/mol
Conjugation energies
Effect of OMe substituent on reaction energies for the rearrangement reactions of rhodasilabenzenes
The blue ones have imaginary frequencies
SiRh
CO 31.63(22.96)
0.0(0.0)
OMe
SiRh
CO35.50(25.90)
0.0(0.0)
OMe Si
RhOC CO
+COOMe
Si
RhOC CO
+COMeO
OC
OC
OC
OC
SiRh
CO
Si
RhOC CO
+CO
Si
RhOC CO
+CO
SiRh
CO
MeO
SiRh
CO
OMe
Si
RhOC CO
+COOMe
SiRhCO
MeO
Si
RhOC CO
+CO
OMe
31.24(22.03)
0.0(0.0)
(16.95)25.89
0.0(0.0)
0.0(0.0)
0.0(0.0)
22.64(13.03)
22.43(12.71) MeO
25.31(25.88)
20.34(21.62)
0.0(0.0)
OC
OC
OC
OC
OC
OC
OC
OC
SiRh
CO
Si
RhOC CO
+CO
MeO
OMeOMe
SiRh
COMeO
Si
RhOC CO
+COMeO
MeO
MeO
SiRh
COMeO
Si
RhOC CO
+COMeO MeO
OMe OMe
0.0(0.0)
0.0(0.0)
0.0(0.0)
19.35(8.75)
15.67(4.44)
12.26(0.714)
MeO
MeOOC
OC
OC
OC
OC
OC
Effect of 2OMe substituent on reaction energies for the rearrangement reactions of rhodasilabenzenes
Effect of PMe3 substituent on reaction energies for the
rearrangement reactions of rhodasilabenzenes.
SiRh
Si
RhOC CO
+CO
SiRh PMe3
Si
RhOC CO
+CO
PMe3
SiRhCO
Si
RhOC CO
+COMe3P
31.24(22.03)
0.0(0.0)
(22.82)31.81
0.0(0.0)
0.0(0.0)
23.62(12.54)
SiRh
Si
RhOC CO
+CO
30.38(21.24)
0.0(0.0)
PMe3
Me3P
SiRh
CO 27.65(18.28)
0.0(0.0)
PMe3 Si
RhOC CO
+COPMe3
Si
RhOC CO
+CO
SiRh
CO
Me3PPMe3
0.0(0.0)
35.33(24.89)
Me3P 1.16(2.86)
-3.56(-2.82)
0.00(0.00)
CO
CO
CO
OC
OC
OC
OC
OC
OC
OC
OC
OC
OC
OC
OC
Effect of PF3 substituent on reaction energies for the rearrangement reactions of rhodasilabenzenes
SiRh
COF3P
Si
RhOC CO
+CO
F3P 0.0(0.0)
9.98(1.42)
Si
RhOC CO
+CO
SiRhCO
F3P
SiRhCO
PF3
Si
RhOC CO
+COPF3
PF3
(27.23)35.12
0.0(0.0)
0.0(0.0)
26.01(16.04)
SiRhCO 27.88
(19.00)
0.0(0.0)
PF3
SiRhCO 25.53
(16.66)
0.0(0.0)
PF3 Si
RhOC CO
+COPF3
Si
RhOC CO
+COF3P
-6.71
(-6.41)
-15.09(-14.88)
0.00(0.00)
OC
OC
OC
OC
OC
OC
OC
OC
OC
OC
Effect of 2PF3 or 3PF3 substituent on reaction energies for the rearrangement reactions of rhodasilabenzenes
SiRhCO
Si
RhOC CO
+CO
PF3 PF3
SiRhCO
Si
RhOC CO
+COF3PF3P
F3P
F3P 0.0(0.0)
0.0(0.0)
14.96(7.72)
4.36(-7.22)
SiRh
CO
Si
RhOC CO
+COF3P
F3P F3P 0.0(0.0)
4.15(-6.42)
PF3 PF3
Si
Si
RhOC CO
+COF3P
F3P
0.0(0.0)
-9.29(-22.66)
SiRhCO
Si
RhOC CO
+COPF3F3P 0.0
(0.0)
7.69(0.47)
PF3
PF3
F3P
F3P
F3P
F3P
F3P
Rh
OCCO
OC
SiRh
CO
Si
RhOC CO
+COF3P
F3P F3P 0.0(0.0)
2.32(-9.68)
F3P PF3PF3
OC
OC
OC
OC
OC
OC
OC
OC
OC
OC
Effect of OMe and PF3 substituent on reaction energies for the rearrangement reactions of rhodasilabenzenes
SiRhCO
Si
RhOC CO
+CO
OMeOMe
SiRhCO
Si
RhOC CO
+COF3PMeO
MeO
F3P 0.0(0.0)
0.0(0.0)
15.60(7.20)
-3.04(-14.87)
Si
Si
RhOC CO
+COF3P
MeO 0.0(0.0)
3.51(-8.04)
Si
RhOC CO
+COOMeF3P 0.0
(0.0)
OMe
F3P
F3P
F3P
Rh
OCCO
OC
Si
F3P
RhOC
COOC
21.87(13.00)
OMe
SiRhCO
Si
RhOC CO
+CO
F3P
F3P 0.0(0.0)
F3P
11.86(1.46)
OMeF3POMe
SiRhCO
Si
RhOC CO
+CO
F3P
F3P 0.0(0.0)
F3P
4.30(-6.57)
F3P
OMe
OMe
OC
OC
OC
OC
OC
OC
OC
OC
path 1
Path 2
TS
Si
Rh
OC
COOC
Si
Rh
OC
COOC
SiRh
OCCO
OC
Si
Rh
OC CO
12.32(15.14)
-2.19(-11.83)
51.10(41.28)
Si
Rh COOC
31.24(22.03)
0.0(0.0)
?
TS2
IN2
IN1
TS1
+CO
SiRh
34.0(35.8)
Si
Rh
OC CO0.0(0.0)
SiRhOC
OC
38.42(41.41)
SiRh
31.24(22.03)
SiRh
OC
OC
CO
OCC O
OCCO
OC
44.38(37.63)
TS2IN1
TS1+CO
1. The thermodynamic of the Silacyclopentadienyl complexes is more stable than Rhodasilabenzene.
2. Computed how the substituents (OMe,PMe3,PF3) on the metallacycle affect the transformation and found that substituents and their locations on the metallacycle have a significant effect on the thermodynamic of the rearrangement reactions.
3. But can not realize the isomerization from Silacyclopentadienyl complexes to Rhodasilabenzenes.
4. Explore the possible pathway for the Rhodasilabenzene to Silacyclopentadienyl complexes.
Result Summary
1. realize the isomerization from Silacyclopentadienyl complexes to Rhodasilabenzenes by using substituents on the metallacycle
2. Find the reaction pathway from Silacyclopentadienyl complexes to Rhodasilabenzenes.
Next work
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Thanks for your attention