The title compound, C(15)H(17)FO, was prepared directly from the aldol condensation of cyclo-octa-none with 4-fluoro-benz-aldehyde, catalysed by Pd(Ni,Ce) in the presence of trimethyl-silyl chloride. The eight-membered ring adopts a boat-chair conformation.

Five new bulky moiety-modified analogues of the sandalwood odorant Polysantol have been synthesized by aldol condensation of appropriate aldehydes with butanone, deconjugative alpha-methylation of the resulting alpha,beta-unsaturated ketones, and reduction of the corresponding beta,gamma-unsaturated ketones. The final compounds were evaluated organoleptically and one of them seemed to be of spe...

The title compound, C(15)H(10)F(N)O(3), was prepared from 2-nitro-acetphenone and 4-fluoro-benzaldehyde by an Aldol condensation reaction. The dihedral angle formed by the two benzene rings is 67.37 (2)°. The crystal structure is stabilized by weak inter-molecular C-H⋯O and C-H⋯F hydrogen bonds.

The first enantiospecific synthesis of akaol A, a marine sesquiterpene quinol, has been achieved. Key steps of the synthetic sequence are the oxidative degradation of (-)-sclareol to a dinorlabdane ketoester, mediated by the ozone-lead(IV) acetate system, the diastereoselective α-methylation of a ketoaldehyde, followed by an intramolecular aldol condensation and the further Diels-Alder cycloadd...

A new heterogeneous catalyst, hydrophobic TiO4-deposited mesoporous silica, has been designed for the efficient Mukaiyama-aldol condensation, a water-participating Lewis acid-catalyzed reaction between a hydrophobic carbonyl compound and silyl enol ether. The prepared catalyst suspended in water exhibited high catalytic performance as a reusable catalyst for the reaction without a surfactant.

The preparation of the crystalline amide 2 is reported. Conjugate addition to 2 proceeded with the expected high diastereocontrol to give 3. This set the stage for subsequent intramolecular alkylidene C-H insertion to give, after ozonolysis and aldol condensation, (-)-mesembrine 1. Amide 2 should be a useful chiron for the enantioselective construction of cyclic quaternary centers.

Saponarin, apigenin 6-C- and 7-O-bis-β-D-glucoside, was synthesized in an overall yield of 37% via 11 steps, which included the C-glycosylation of 2,4-O-dibenzylphloroacetophenone, the introduction of a cinnamoyl residue by aldol condensation, the formation of a flavone by regioselective deprotection, and oxidative ring-closure to the final regioselective deprotection and stereoselective O-glyc...

The title compound, C(14)H(11)ClO(2), was prepared from 4-chloro-hypnone and 5-methyl-furfural by an aldol condensation reaction. The dihedral angle formed between the two benzene rings is 7.71 (2)°. The crystal structure is stabilized by C-H⋯O inter-actions.

A general synthetic approach to the isoprostanes has been established, based on intermolecular aldol condensation of a diazo ketone with an unsaturated aldehyde, followed by cyclization of the resulting diazo ketone to the cyclopropane. Subsequent kinetic opening with thiophenol followed by further elaboration then leads to the isoprostane. The history of this approach and the details of its de...

Treatment of the diol 6 with KH and 18-C-6 at room temperature gives the cyclopentenone 7 in good yields. Mechanistic analysis reveals that this is the first case of an anionic oxy retro-ene reaction followed by a tandem intramolecular aldol condensation. Reaction: see text.