The attempted synthetic methods to produce some macrocyclic compounds have been made via ring expansion reactions. The studies were divided into two categories. 1) Ring expansion via free radical. A synthesis of muscone fall into two routes. In the first route, 1-(2-methyl-2-propenyl)cyclododecanol was the key intermediate which could be readily synthesized by Grignard reaction of cyclododecanone with 3chloro-2-methylpropene (Scheme A). In the second route, 2-(2-methyl-3-halopropyl)cyclododecanone (R=CH3, R"=H or R=CH2, R"=COOEt) were the key intermediate. (Scheme B) 2) Ring expansion via anionic intermediate. A synthesis of muscone fall into two routes. In the first route, 1-(2-methyl-2,3-oxypropyl)cyclododecanol was the key intermediate which could be synthesized by epoxidation of 1-(2-methyl-2-propenyl)cyclododecanol (Scheme C). In the second route, the key intermediate was expected to be obtained from 2-carbethoxy-2-(2-methyl-2-propenyl)cyclododecanone. (Scheme D)