Process for preparing octahydro-2(1h)-naphthalenone derivatives

A process for the preparation of a compound of formula

• wherein the bold and hatched lines indicate a relative or absolute configuration comprising the steps of
• a) oxidative cleavage of compound of formula
• in a form of any one of its stereoisomers or a mixture thereof, and wherein X represents a vinyl, a CHO, a COOH, a C(═O)OR1 or a CH2OR2 group wherein R1 represents a C1-6 alkyl group and R2 represents a hydrogen atom, a benzyl group, a C(═O)Ra group, a C(═O)ORb group, a C(Rc)2ORd group or a Si(Rd)3 group wherein Ra is a hydrogen atom or a C1-6 alkyl group, Rb is a C1-6 alkyl group, Rc, independently from each other, are a hydrogen atom or a C1-2 alkyl group and Rd is a C1-4 alkyl group;
• or one Rc and Rd, when taken together, form a C4-5 oxacycloalkyl group;
• into an intermediate of formula
• in the form of any one of its stereoisomers or a mixture thereof, and wherein X′ represents a CHO, a COOH, a C(═O)OR1 or a CH2OR2 group and R1 and R2 have the same meaning as defined above;
• and
• b) the conversion of the intermediate of formula (III) to the compound of formula (I).