Quantitative addition of organolithium and Grignard reagents to camphor (1) and fenchone (2) proceeds via precomplexation of the ketone with CeCl3 at room temperature. Excellent addition using catalytic or substoichiometric amounts of CeCl3 is demonstrated for the first time.

The new optically active 1,3-diols 5-8 with (1R)-(+)-camphor and (1R)-(-)-fenchone skeleton were synthesized in high yields from the homoallylic alcohols 1-4 using a very effective ozonolysis followed by reduction. The absolute configuration of (1R, 2S, 12R)-6a was determined by a single crystal X-ray study.

The aldehyde 3, prepared by ozonolysis of 2-allyl-2-nitrocyclododecanone, gave the ring-enlargement product 5 (85%) by treatment with (i-Bu)(2)AlH. Its transformation to the tetradecano-14-lactone (8) via the aldol ester 6 and other routes (best is reduction with Bu(3)SnH, AIBN, toluene) was difficult. Remarkable is the smooth denitrification of 3 (loss of HN0(2)) to the conjugated dione 4 by chromatography on silica gel or base treatment.

An improved strategy for synthesis of 1-chloro-bicyclo[2.2.2]octane is described in which the key compounds 1-norbornyl substituted ethyl formate (3) or 1-norbornylcarbaldehyde (7) were prepared from 1-norbornyllithium (1). The latter appeared as a useful precursor for the synthesis of various organic bridgehead substituted derivatives.