[rentj]

Is the first step of adding SOCl2 needed for this synthesis? Because the excess LAH in the second step will do the same thing, which is producing a primary alcohol. Thank you

[Babcock_Hall]

I am not sure what would happen if you left out the thionyl chloride.  If you are following a literature preparation, I see no reason to deviate from it.

[Hunter2]

I think with the Thionylchloride you create first the cyclopentylcarboxylchloride, this should be reduced to the aldehyde to obtain in the end the Acetale. If you get total reduction to the cyclopentylmethanol then it is not possible to fo further.

[rolnor]

I think with the Thionylchloride you create first the cyclopentylcarboxylchloride, this should be reduced to the aldehyde to obtain in the end the Acetale. If you get total reduction to the cyclopentylmethanol then it is not possible to fo further.

But there is PCC in the reagent list, do you know what that is for? Can you reduce an acid chloride to aldehyde with LAH?

[Hunter2]

It's an oxidiser. To oxidise Alkohol to Aldehyde. Yes with LAH the Reduction goes direction to the Alkohol.
But if so then LAH can be used to refuse the carbonic acid. Maybe SOCl2 is only used to remove water.

[Babcock_Hall]

@OP, Is this a homework assignment, or are you doing this reaction in a laboratory?

[rolnor]

It's an oxidiser. To oxidise Alkohol to Aldehyde. Yes with LAH the Reduction goes direction to the Alkohol.
But if so then LAH can be used to refuse the carbonic acid. Maybe SOCl2 is only used to remove water.

The acid chloride is reduced to alcohol, then oxidised to aldehyde. It's not common to reduce a carboxylic acid to a alcohol with LAH i think. I have never seen this, I don't think it's possible.

[Hunter2]

In this Chart its possible

https://upload.wikimedia.org/wikipedia/commons/thumb/3/30/LAH_rxns.png/550px-LAH_rxns.png

[Babcock_Hall]

@OP,
Can you explain why an acid chloride is easier to reduce than an acid using fundamental concepts from organic chemistry?

[rolnor]

In this Chart its possible

https://upload.wikimedia.org/wikipedia/commons/thumb/3/30/LAH_rxns.png/550px-LAH_rxns.png

Yes, I was not 100% sure. Maybe you need to boil the solution for some time

[rolnor]

Here is another example. It seems unmotivated to convert the acid  to acid chloride.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map%3A_Organic_Chemistry_%28Vollhardt_and_Schore%29/19%3A_Carboxylic_Acids/19.11%3A_Reduction__of_Carboxylic_Acids__by_Lithium_Aluminum_Hydride