Permethyl cyclopentanone synthesis

The very high nucleophilicity of a-heterosubstituted a-lithiocyclopropanes and of a-lithioalkyl selenides, even those bearing two alkyl groups on the, carbanionic center, permits the stepwise construction of a cyclopentane ring possessing several quaternary centers in vicinal positions with respect to one another by two successive ring expansion reactions from a suitably functionalyzed cyclopropane 135,224) (Schemes 98, 101). This feature has been used by Fitjer2240 for the synthesis of permethyl cyclobutanone, permethyl cyclopentanone, and even permethyl cyclohexanone, as well as for the preparation of previously unknown permethylcyclohexane. 

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See also in sourсe #XX -- [ , , ]

See also in sourсe #XX -- [ , , ]

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