Cyclopropanes, hydrogenolysis alkyl substituted

The pattern of bond cleavage in the hydrogenolysis of aziridines generally follows that observed with cyclopropanes. Alkyl substituted aziridines are cleaved at the most accessible C-N bond. This provides a good route to the production of molecules having a primary amine group on a tertiary carbon (Eqn. 20.48). ... 

As illustrated in Fig. 20.1, the C-C bond that is broken in the hydrogenolysis of alkyl cyclopropanes is that one between the two least substituted carbon atoms of the ring. With unsymmetrical 1,2-dialkyl-cyclopropanes (1, R iR ) the bond adjacent to the smaller alkyl group is preferentially cleaved. When coupled with the facile cyclopropanation of alkenes, the hydrogenolysis of alkyl cyclopropanes over platinum oxide has served as a useful means of introducing a methyl group onto a tertiary carbon atom as illustrated by the preparation of tert-butyladamantane (3) (Eqn. 20.1) and the 9-methyldecalins, 5 and 6 (Eqn. 20.2). > ... 

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