1-Adamantanecarbonitriles are very active in the Stephen reaction, which allows synthesis of the corresponding aldehydes in high yields. Electron-acceptor substituents in the 3 position of the adamantine nucleus exert almost no effect on the yield of aldehydes. Separation of the nitrile group and the adamantane nucleus by one methylene group results in a complete loss of reactivity. A quantitative study of the reactivity of the synthesized aldehydes in the oximation reaction was performed.