(3-Hydroxy-3-methylbutyn-1-yl)cycloalkan-1-ols in the Ritter Reaction

(3-Hydroxy-3-methylbutyn-1-yl)cycloalkan-1-ols were prepared by the action of (2-lithiooxy-2-methylbutyn-3-yl)lithium on cyclopentanone, cyclohexanone, cycloheptanone, and cyclododecanone. The products react with acetonitrile under Ritter reaction conditions. Therewith, in the presence of 8 g-equiv of sulfuric acid, a 2:1 mixture of 1-acetylamino-1-(2-acetylamino-2-methylbutyn-3-yl)cycloalkanes and 1-acetylamino-1-(3-acetylamino-3-methylbutyryl)cycloalkanes is formed, whereas in the presence of 2 g-equiv of the acid, a mixture of 1-acetylamino-1-(2-acetylamino-2-methylbutyn-3-yl)cycloalkanes and 1-acetylamino-1-(3-methyl-2-butenoyl)cycloalkanes in the same ratio.