Consider the following reactions
(1) `(CH_3)_3"CC"H(OH)CH_3overset("conc".H_2SO_4)rarr`
(2) `(CH_3)_2"CHCH(Br)CH_(3)overset(conc.KOH)rarr`
(3) `(CH_3)_2"CHCH(Br)CH_(3)overset((CH_3)_3CO^(-) Koplus)rarr`
(4) `(CH_3)_2underset( "OH ")underset(" | ")(C-CH_2)-CHOoverset(Delta)rarr`
Which of these reaction(s) will produce Saytzeff product?

Options

A. (1) , (2) and (4)
B. (3) only
C. (4) only
D. (2) and (4)

Answer

To determine which reactions produce Saytzeff products, we need to analyze each reaction step by step.

### Step 1: Analyze Reaction 1
**Reaction:** `(CH₃)₃C(OH)CH₃ + conc. H₂SO₄ → ?`

1. **Identify the structure:** The starting compound is tert-butyl alcohol, which has a hydroxyl (-OH) group.
2. **Dehydration reaction:** When treated with concentrated sulfuric acid, the -OH group is removed, leading to the formation of a carbocation.
3. **Carbocation stability:** A tertiary carbocation is formed, which is stable.
4. **Rearrangement:** A 1,2-methyl shift can occur to stabilize the carbocation further.
5. **Formation of alkene:** The elimination of a proton leads to the formation of a double bond.
6. **Product:** The major product is an alkene with more substituents on the double bond, which is a Saytzeff product.

### Step 2: Analyze Reaction 2
**Reaction:** `(CH₃)₂CHCH(Br)CH₃ + conc. KOH → ?`

1. **Identify the structure:** The starting compound is an alkyl bromide.
2. **Base-induced elimination:** Concentrated KOH acts as a strong base, promoting the elimination of HBr.
3. **Formation of alkene:** The base abstracts a proton from the carbon adjacent to the carbon bearing the bromine, leading to the formation of a double bond.
4. **Product:** The major product will be the more substituted alkene, which is a Saytzeff product.

### Step 3: Analyze Reaction 3
**Reaction:** `(CH₃)₂CHCH(Br)CH₃ + (CH₃)₃CO⁻ K⁺ → ?`

1. **Identify the structure:** The starting compound is again an alkyl bromide.
2. **Bulky base:** The base used here is a bulky base (tert-butoxide), which prefers to abstract the least hindered hydrogen.
3. **Formation of alkene:** The bulky base will remove the hydrogen from the less substituted carbon, leading to the formation of a double bond.
4. **Product:** This will result in the formation of the less substituted alkene, which is a Hofmann product, not a Saytzeff product.

### Step 4: Analyze Reaction 4
**Reaction:** `(CH₃)₂C(OH)CH₂CHO + Δ → ?`

1. **Identify the structure:** The starting compound is a secondary alcohol with an aldehyde group.
2. **Dehydration reaction:** Heating will lead to dehydration, removing -OH and -H to form a double bond.
3. **Formation of alkene:** The double bond will form between the carbon bearing the -OH group and the adjacent carbon.
4. **Product:** The major product will be the more substituted alkene, which is a Saytzeff product.

### Conclusion
**Saytzeff Products:**
- Reaction 1 produces a Saytzeff product.
- Reaction 2 produces a Saytzeff product.
- Reaction 4 produces a Saytzeff product.
- Reaction 3 produces a Hofmann product.

### Final Answer:
Reactions 1, 2, and 4 will produce Saytzeff products.

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