[herrhansen]

Hello guys and girls.

I was asked to solve the synthesis attached. The teacher proposed the synthesis handwritten and I supposed the one in the bottom. I cant see how the one he proposed is correct? It was only allowed to use one carbon organic compounds + inorganics to carry out the synthesis.

Could anyone help please?

Thanks in advance.

[sjb]

Hello guys and girls.

I was asked to solve the synthesis attached. The teacher proposed the synthesis handwritten and I supposed the one in the bottom. I cant see how the one he proposed is correct? It was only allowed to use one carbon organic compounds + inorganics to carry out the synthesis.

Could anyone help please?

Thanks in advance.

I only see one scheme, is there one missing? The handwritten one is, I suppose a little confusing as in the final step the ring also rotates 180 degrees in the plane of the page.

S

[rucik5]

Hi. The first step is acid catalyzed acetalisation and esterification, where the oxygen of the aldehyde is protected and carboxylic acid converted to an ester. Now, excess of the Grignard reagent on the ester converts it to a tertiary alcohol - the first equivalent kicks out the -OR to give you the ketone and second equivalent yields the alcohol. Deprotection of the acetal yields your product - but as sjb said already, it's rotated by 180°.

I can not see your attempt on the PDF.