Ab initio study of the mechanism of forming a spiro-Si-heterocyclic ring compound involving Ge from H2Ge=Si: and acetaldehyde

The H2Ge=Si: and its derivatives(X2Ge=Si:, X = H, Me, F, Cl, Br, Ph, Ar??) is a new species. Its cycloaddition reactions is a new area for the study of silylene chemistry. The mechanism of the cycloaddition reaction between singlet H2Ge=Si: and acetaldehyde has been investigated with MP2/6-311++G** method, From the potential energy profile, it can be predicted that the reaction has a dominant reaction pathway. The reaction rule presented is that the two reactants firstly form a four-membered Ge-heterocyclic ring silylene through the [2+2] cycloaddition reaction. Because of the 3p unoccupied orbital of Si: atom in the four-membered Ge-heterocyclic ring silylene and the ? orbital of acetaldehyde form a ??p donor-acceptor bond, the four-membered Ge-heterocyclic ring silylene further combines with acetaldehyde to form an intermediate. Then the intermediate isomerizes to a spiro-Si-heterocyclic ring compound involving Ge via a transition state.

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Ab initio study of the mechanism of formation of a spiro-Sn-heterocyclic ring compound by the cycloaddition reaction of H2C=Sn: and ethylene

Journal of the Serbian Chemical Society ◽

10.2298/jsc180603072t ◽

2019 ◽

Vol 84 (3) ◽

pp. 293-301

Author(s):

Xiaojun Tan ◽

Xiuhui Lu

Keyword(s):

Cycloaddition Reaction ◽

Heterocyclic Ring ◽

Membered Ring ◽

Ab Initio Study ◽

Mechanism Of Formation ◽

Potential Energy Profile ◽

Unoccupied Orbital ◽

Reaction Rule ◽

Donor Acceptor ◽

First Time

X2C=Sn: (X = H, Me, F, Cl, Br, Ph, Ar?) are new species of chemistry. The cycloaddition reactions of X2C=Sn: is a new study field of stannylene chemistry. The mechanism of cycloaddition reaction of singlet H2C=Sn: with ethylene is studied for the first time using the MP2/GENECP (C, H in 6-311++G**; Sn in LanL2dz) method in this paper. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction rule presented is that the 5p unoccupied orbital of tin in H2C=Sn: sidewise overlaps with the bonding ? orbital of ethylene resulting in the formation of an intermediate. The instability of the intermediate makes it isomerise to a four-membered ring stannylene. As the 5p unoccupied orbital of the Sn atom in the four-membered ring stannylene and the ? orbital of ethylene form a ??p donor?acceptor bond, the four-membered ring stannylene further combines with ethylene to form another intermediate, and this intermediate further isomerises to a spiro-Sn-heterocyclic ring compound. The Sn in the spiro-Sn-heterocyclic ring compound is combined with adjacent atoms by sp3 hybridization. The results of this study reveal the mechanism of cycloaddition reaction of X2C=Sn: with symmetric ?-bond compounds.

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Theoretical study of the formation of a spiro-Sn-heterocyclic compound by cycloaddition reaction of Me2C=Sn: and ethene

Heterocyclic Communications ◽

10.1515/hc-2018-0129 ◽

2018 ◽

Vol 24 (6) ◽

pp. 311-315 ◽

Cited By ~ 1

Author(s):

Xiaojun Tan ◽

Xiuhui Lu

Keyword(s):

New Species ◽

Intermediate Product ◽

Theoretical Study ◽

Cycloaddition Reaction ◽

Heterocyclic Ring ◽

Membered Ring ◽

Energy Profile ◽

Potential Energy Profile ◽

Donor Acceptor ◽

First Time

AbstractX2C=Sn: compounds (X=H, Me, F, Cl, Br, Ph, Ar) are new species. The cycloaddition reactions of X2C=Sn: are also a new study field of unsaturated stannylene chemistry. The mechanism of cycloaddition reaction between singlet Me2C=Sn: and ethene was investigated for the first time using the MP2/GENECP (C, H in 6-311++G**; Sn in LanL2dz) method. From the potential energy profile, it was predicted that the reaction has one dominant channel in which the 5p unoccupied orbital of Sn: in Me2C=Sn: and theπorbital of ethene form aπ→pdonor-acceptor bond in an intermediate product. Instability of the intermediate product results in its isomerization to a four-membered ring of stannylene. The four-membered stannylene further combines with ethene to form another intermediate product that further isomerizes to a spiro-Sn-heterocyclic ring compound.

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An ab initio study of the mechanism of formation of a silicic bis-heterocyclic compound from silylenesilylene (H2Si=Si:) and ethene

Journal of the Serbian Chemical Society ◽

10.2298/jsc110115119l ◽

2012 ◽

Vol 77 (1) ◽

pp. 75-81

Author(s):

Xiuhui Lu ◽

Leyi Shi ◽

Yongqing Li ◽

Zhina Wang

Keyword(s):

Potential Energy ◽

Heterocyclic Compound ◽

Singlet State ◽

Reaction Pathway ◽

Cycloaddition Reaction ◽

Membered Ring ◽

Energy Profile ◽

Ab Initio Study ◽

Mechanism Of Formation ◽

Potential Energy Profile

The mechanism of the cycloaddition reaction of the formation of a silicic bis-heterocyclic compound between singlet state silylenesilylene (H2Si=Si:) and ethene wasi investigated by the CCSD(T)//MP2/6-31G* method. From the potential energy profile, it can be predicted that the reaction has one dominant reaction pathway. The presented rule of the dominant reaction pathway is that the [2+2] cycloaddition effect of the two reactants leads to the formation of a four-membered ring silylene (INT1). When the four-membered ring silylene (INT1) interacts with ethene, due to sp3 hybridization of the Si: atom in four-membered ring silylene (INT1), the four-membered ring silylene (INT1) further combines with ethene to form a silicic bis-heterocyclic compound (P2).

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Ab initio study of mechanism of forming a Si-heterocyclic spiro-Sn-heterocyclic ring compound by cycloaddition reaction of Me2Si=Sn: and ethene

Progress in Reaction Kinetics and Mechanism ◽

10.1177/1468678319825898 ◽

2019 ◽

Vol 44 (2) ◽

pp. 114-121

Author(s):

Xiaojun Tan ◽

Xiuhui Lu

Keyword(s):

Singlet State ◽

Cycloaddition Reaction ◽

Chemical Species ◽

Heterocyclic Ring ◽

Basis Set ◽

Cycloaddition Reactions ◽

Unoccupied Orbital ◽

Donor Acceptor ◽

Moller Plesset ◽

First Time

X2Si=Sn: (X = H, Me, F, Cl, Br, Ph, Ar, etc.) are a new chemical species. The cycloaddition reactions of X2Si=Sn: are a new field of stannylene chemistry. The mechanism of the cycloaddition reaction between singlet state Me2Si=Sn: and ethene has been investigated for the first time here using second-order Møller-Plesset perturbation theory together with the 6-311++G** basis set for C, H and Si atoms and the LanL2dz basis set for Sn atoms. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction process presented is that the 5p unoccupied orbital of Sn in Me2Si=Sn: and the π orbital of ethene form a π → p donor–acceptor bond resulting in the formation of an intermediate. The instability of this intermediate makes it isomerize to a four-membered Si-heterocyclic ring stannylene. Because the 5p unoccupied orbital of the Sn atom in the four-membered Si-heterocyclic ring stannylene and the π orbital of ethene form a π → p donor–acceptor bond, the four-membered Si-heterocyclic ring stannylene further combines with ethene to form another intermediate. Because the Sn atom in this intermediate assumes sp3 hybridization after the transition state, the intermediate isomerizes to a Si-heterocyclic spiro-Sn-heterocyclic ring compound. This result indicates the modes of cycloaddition reactions between X2Si=Sn: and symmetric π-bonded compounds, i.e. this study opens up a new field for stannylene chemistry.

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