
%0 Journal Article
%A Hamon, DPG 
%A Taylor, GF 
%T The synthesis of Tetracyclo[5,3,1,0<sup>3,5</sup>,0<sup>4,9</sup>]undecan-2-one and the acid-catalysed and reductive cleavages of the cyclopropyl ring
%J Australian Journal of Chemistry
%D 1975/10/01
%V 28
%N 10
%P 2255-2263
%K 
%R https://doi.org/10.1071/CH9752255
%U https://www.publish.csiro.au/paper/CH9752255 
%X Tetracyclo[5,3,1,03,5,04,9]undecan-2-one (2,4-dehydro-5-homoadamantanone) (3) was synthesized by copper-catalysed intramolecular insertion of a diazoketone into a double bond. Acid-catalysed opening of the cyclopropyl ring in aqueous acetic acid cleaved the C3-C4 bond to give a mixture of exo-7-hydroxytricyclo[4,3,1,13,8]undecan-4-one (13) and its acetate (12). Under the same conditions except for the presence of bromide ion, a mixture of (12), (13) and exo-7- bromotricyclo[4,3,1,13,8]-undecan-4-one (17) was obtained. Reduction of (17) with LiAlH4 gave homoadamantanol. Reduction of (3) with lithium in liquid ammonia gave cleavage of the C 3-C 5 bond to afford tricyclo[5,3,1,04,9]-undecan-2-one (4), the structure of which was confirmed by independent synthesis. 
