PROCESS FOR THE PREPARATION OF BICYCLIC ENON COMPOUNDS

This invention relates to a process for the preparation of a racemic or optically active compound of the general formula V (V) wherein R stands for a hydrogen, acyl, alkyl or silyl, R1 and R2 together form an oxo group or R1 stands for a lower alkoxy, optionally substituted with one, two or three halogen atom(s) and R2 stands for a hydrogen, Q stands for a straight or branched chained alkyl having one to 10 carbon atoms, alkenyl containing one double bond or alkenyl containing one triple bond, which comprises reacting a racemic or optically active lactone diol derivative of the general formula III (III) wherein R1 and R2 have the same meaning as defined above - with an oxidant, then further reacting the thus obtained aldehyde of the general formula II (II) wherein R1 and R2 have the same meaning as defined above - with a phosphorous compound of the general formula VI (VI) or VII (VII) wherein R3 stands for a lower alkyl and Q has the same meaning as defined above, preferably without separation, if desired, alkylating, acylating or silylating the hydroxyl of the obtained compounds of the general formula VIII (VIII) wherein R1, R2 and Q have the same meaning as defined above, and, if desired, preparing optically active compounds of the general formula V by the resolution of a racemic compound of the general formula V. The compounds obtained are useful as starting materials for the preparation of prostaglandine intermediates of the formula (I) These intermediates are useful in the Corey prostaglandine synthesis in which prostaglandine derivatives are produced which have outstanding biological activity of the endogeneous tissue-hormones.