| abstract |
(57) Abstract: The method according to the present invention can provide a novel route to provide an α-substituted ring system which may optionally have further substituents in a small number of reaction steps. SOLUTION: Formula (II) Wherein R, R 1 , R 2 and n have the meaning given in the description, and furthermore at least one double bond The process for preparing at least α-substituted ring systems which may be substituted by two groups R comprises the process of formula (I) Wherein R, R 1 and n are as defined in the description, respectively, which includes subjecting the compound represented by the formula: to a metathesis reaction in the presence of a noble metal catalyst. |