Hydroxy alkynoic acid

Isomerization of triple bonds.1 This base is easier to prepare than potassium 3-aminopropylamide, but is less effective for isomerization of triple bonds to the terminal position. However when used together with potassium l-butoxide, isomerization of triple bonds occurs in 1-4 hours at 25°. Isomerization of acetylenic acids results in terminal alkynoic acids and 3,5-dienoic acids. However, acetylenic alcohols (primary or secondary) can be isomerized to w-hydroxy-l-alkynes in high yield. 

The precursor has the same carbon skeleton as the designated starting material. All that is necessary is to hydrogenate the double bond of the alkynoic acid to the cis alkene. This can be done by using the Lindlar catalyst. Cyclization of the hydroxy acid to the lactone is spontaneous. 

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