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Developments in the Wittig and Horner–Wadsworth–Emmons (HWE)-olefination of aldehydes and ketones with stabilised phosphoranes or phosphonates provide opportunities for multicomponent reactions and...

Benzamides were converted into benzonitriles with BrCCl3–PPh3–Et3N in CH2Cl2 in an Appel-type reaction. Benzaldoximes could be transformed to benzonitriles under identical conditions. It was found that the reaction system BrCCl3–(2 equiv.)PPh3 was also suitable for these transformations with PPh3 replacing Et3N.

The synthesis of a number of structurally related estradiol-17α-ylmethyl hydroxycinnamides and of one novel estra-1,3,5(10),6-tetraen-3-ol-17β-yl hydroxycinnamide is described, using a microwave assisted amidation of steroidal amines with pentafluorophenol activated, non-protected hydroxycinnamic acids as a key step. A selection of the compounds and of other estra-1,3,5(10)-trien-3-ol 17β-yl hydroxycinnamides was screened against 60 human cancer cell lines, derived from nine neoplastic diseases. From the overall results of the screening, it could be inferred that dihydroxycinnamide derived estradiol conjugates exhibit a better cytotoxic profile when compared with hydroxymethoxycinnamide derived estradiol conjugates.

Oligocycles with a 7-thiabicyclo[2.2.1]hept-5-ene unit have been prepared stereoselectively by cycloaddition of thiophene S-oxides to alkenes and subsequent deoxygenation of the sulfoxy bridge of the cycloadducts with PBr3.

Platelet, tubular and herringbone carbon nanofibres were doped with Pd under various conditions. The catalysts were analysed for their Pd-content and as to the size distribution of the Pd particles. The Pd-doped carbon nanofibres were screened for their catalytic activity in the Suzuki–-Miyaura cross coupling and in the Heck–-Mizoroki reaction.

The photooxygenation of thiophenes, benzo[ b]thiophenes and dibenzothiophenes is discussed, especially in view of the oxidative removal of these S-containing contaminants from fuels. Furthermore, the photochemistry of the intermediates and the products from these processes is detailed. Finally, an account is given of the electrooxidation of thiophenes and derivatives to the corresponding sulfoxides and sulfones as well as of the electrochemical behaviour of the intermediate thiophene S-oxides.

Upon reaction with an excess of 2,2-dimethylpropane-1,3-diol (neopentyl glycol, NPG) under acid catalysis, indanones and tetralones yield indenes and dihydronaphthalenes, respectively. The reaction can also be carried out with butane-1,3-diol.

Upon reaction with an excess of 2,2-dimethylpropane-1,3-diol (neopentyl glycol) under acid catalysis, estrones form 17-O-[2′,2′-dimethyl-2′-(5″,5″-dimethyl-1″,3″-dioxanyl)ethyl] substituted estra-3, 17β-diols. The reaction represents a formal reduction of a keto function under acidic conditions in the absence of a metal.

The reactivity of a number of chloroarenes was investigated and chloro–nitroarenes were found to undergo facile arylation with Pd(PPh3)4 / [Pd(PPh3)2Cl2/n·PPh3] as catalyst. Furthermore, 4–chlorobenzaldehyde underwent arylation under the conditions, albeit with a higher catalyst loading.

Estrone has been converted to an aminopyrimidino [17,16-e]-annelated estrane derivative. A number of amino acids, dipeptides and tripeptides have been linked to the aminopyrimidino unit of the annelated steroid. The tripeptide motifs may be used for the complexation of metals, such as of technetium as a radiolabel for the potential detection of estrogen positive breast cancer cells.

The reaction of 1-ethynyl-2-vinyl-3,4-dihydronaphthalenes and 1-ethynyl-2-vinylnaphthalenes over RuCl2(p-cymene) PPh3 leads to 9,10-dihydrophenanthrenes and phenanthrenes in those cases where the ethynyl group in the substrates carries a terminal proton. When 1-phenylethynyl-2-vinyl-3,4-dihydronaphthalenes or 1-phenylethynyl-2-vinylnaphthalenes are reacted over Pt(PPh3)4, 1-methylene-1H-benz[e]-4,5-dihydroindenes and 1-methylene-1H-benz[e]indenes are formed.

Tetracyclones are transformed to a mixture of diacylstilbenes and α-pyrones, when they are heated in diphenylether saturated with oxygen.

A number of α-alkoxyestradiols were prepared through LiAlH4 reduction of a suitably protected 6α,7α-epoxyestra-1,3,5(10)-trien-3-ol-17-one, alkylation of the resultant 7α-hydroxyestra-1,3,5(10)-trien-3-ol-17-one derivative and subsequent transformation of the C17 functionality. The stereochemistry of the products was investigated by 2D NMR spectroscopy.

In the presence of platinum on carbon (Pt/C), (E)-1,3-diaryl- and (E)-1,3-diheteroaryl- prop-2-en-1-ols react with primary and secondary alcohols to give (E)-1,3-diaryl- and (E)-1,3-diheteroaryl- prop-2-enyl ethers.

Fluorinated benzaldehydes undergo solventless Wittig olefination with stabilised phosphoranes. Even with less reactive, stabilised phosphoranes, such as acetylmethylidenetriphenylphosphorane, the reactions have been found to be exothermic.

The synthesis of estranes bearing an additional heterocyclic ring attached to C-16 and C-17 is reviewed. Potential applications and biological activities of the compounds are described.

The X-ray crystal structures of a number of 6-ketoestra-1,3,5(10)-trien-17-ones and 6-ketoestra-1,3,5(10)-triene-17-one 17-O,O-acetals have been determined and the effect of the acetal group on the conformation of rings B and D are discussed.

Bromoarylcarbaldehydes, bromoheteroarylcarbaldehydes, and bromoalkenals can be subjected to a one pot Sonogashira coupling–Wittig olefination reaction to give easy access to molecules with extended pi-systems.

Bromoarylcarbaldehydes and bromothienylcarbaldehydes undergo Suzuki cross coupling and Wittig reactions in a one pot procedure to give olefins with extended pi systems. Dihaloarenes can be transformed in a double Wittig – / double Suzuki cross coupling reaction to yield functionalised terphenyls.

Raney Ni–AI alloy in a dilute aqueous alkaline solution has been shown to be a powerful reducing agent and is highly effective for the reduction of alkylbenzils and alkoxybenzils to afford the corresponding 1,2-diarylethers at 90°C, in the absence of organic solvents. 4,4′-Dinitrobenzil was transformed selectively to 1,2-bis(4-aminophenyl)-ethane.

Raney Ni-Al alloy in a dilute aqueous alkaline solution has been shown to be a very powerful reducing agent and is highly effective for the reductive dehalogenation of polyhalogenated phenols and aromatic ring hydrogenation of phenols to the corresponding cyclohexanols.

Raney Ni–Al alloy in a dilute aqueous alkaline solution has been shown to be a very powerful reducing agent in the hydrogenation of phenol and alkylated phenols to the corresponding cyclohexanol derivatives.

A number of 7-ω-carboxamidoalkyl-substituted estra-1,3,5(10),6-tetraenes as potential ligands for the estrogen receptor ERα have been prepared using either a conjugate addition of α,ω-iodoalkanenitriles or a Michael addition to steroidal ketone 3 as the key step.

Substituted dibenzothiophene and bis-dibenzothiophene S-oxides were prepared and submitted to photolysis. The rate of deoxygenation of the molecules under photoirradiation was found to be highly dependent on their substitution pattern.

Pinacol coupling reaction of several aromatic dialdehydes 1a-d using inexpensive aluminum powder as a reductive reagent in aqueous NaOH-methanol media afforded dimeric compounds 2a-d as main products, in which only one carbonyl group of 1 was reduced.