Syntheses of the previously unknown 2-aminocyclobutanols are described.The cis-isomer (5) is obtained in two steps by photosensitized cycloaddition of 4-oxazolin-2-one (1) or its acetyl derivative 2 to ethylene and subsequent alkaline hydrolysis of the adducts.Synthesis of the trans-isomer (6) is achieved by catalytic hydrogenation of trans-2-azidocyclobutanol (19), which is available in two steps from the cyclic orthobenzoate 12 and -acetate 13, resp., of cis-1,2-cyclobutandiol (11).