Which of the following reactions can be used to form `Si - C` bond?

Options

A. `(CH_(3))_(2) SiCl_(2) + CH_(3)MgCl`
B. `(CH_(3))_(3) SiCl + CH_(3)MgCl`
C. `CH_(3)Li + SiCl_(4)`
D. `CH_(3)Cl + Si + Cu`

Answer

To determine which reactions can be used to form a Si-C bond, we will analyze each given reaction step by step.

### Step 1: Analyze the first reaction
The first reaction involves the interaction of CH3H2 (which can be interpreted as CH4, methane) and SiCl2 with CH3MgCl (a Grignard reagent).

- **Reaction**: CH3MgCl + SiCl2
- **Mechanism**: The CH3- (methyl anion) from CH3MgCl attacks the electropositive silicon atom in SiCl2, displacing a chloride ion (Cl-).
- **Product**: This results in the formation of CH3SiCl (methylsilane).

### Step 2: Analyze the second reaction
The second reaction is similar to the first one but involves CH3H2SiCl and MgCl.

- **Reaction**: CH3H2SiCl + MgCl
- **Mechanism**: Again, CH3- attacks the silicon atom, leading to the removal of a chlorine atom.
- **Product**: This also results in the formation of a Si-C bond.

### Step 3: Analyze the third reaction
The third reaction involves CH3Li and SiCl4.

- **Reaction**: CH3Li + SiCl4
- **Mechanism**: In this case, CH3- from CH3Li attacks the silicon atom in SiCl4, displacing one of the chlorine atoms.
- **Product**: This forms CH3SiCl3 (methyltrichlorosilane) and LiCl as a byproduct.

### Step 4: Analyze the fourth reaction
The fourth reaction involves CH3Cl and silicon with copper at high temperatures.

- **Reaction**: CH3Cl + Si + Cu
- **Mechanism**: At elevated temperatures, CH3Cl reacts with silicon in the presence of copper, leading to the formation of CH3SiCl3 and other products.
- **Product**: This reaction also results in the formation of Si-C bonds.

### Conclusion
After analyzing all four reactions, we can conclude that all of them can be used to form Si-C bonds.

### Final Answer
All four reactions can be used to form Si-C bonds.

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