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A two-step synthesis of indoles that is suitable for use on a large scale is described. The general applicability of this methodology has also been briefly explored.

Methyllithium, in the presence of excess methyl iodide, can be used to convert suitably substituted aromatic bromides to the corresponding toluenes under mild conditions and in high yield.

A number of aryl halides (X=Cl, Br, I) can be converted to the corresponding toluenes in an operationally simple manner using trimethylboroxine (TMB) as a partner for palladium-catalysed Suzuki–Miyaura coupling.

Treatment of 3-methoxycarbonylindole with N -chlorosuccinimide followed by a range of alkenols yields 3-allylated-2-oxindoles in good yield, via a novel addition–Claisen rearrangement sequence.

Short syntheses of Gabosines C (1) and E (3), starting from D-ribose are reported. The syntheses employ an intramolecular nitrile oxide cycloaddition to generate the carba-sugar skeleton, and result in the first total syntheses of unnatural (+)-Gabosine C and natural (+)-Gabosine E.

Short syntheses of Gabosines C (1) and E (3), starting from D-ribose are reported. The syntheses employ an intramolecular nitrile oxide cycloaddition to generate the carba-sugar skeleton, and result in the first total syntheses of unnatural (+)-Gabosine C and natural (+)-Gabosine E.

Treatment of 3-methoxycarbonylindole with N -chlorosuccinimide followed by a range of alkenols yields 3-allylated-2-oxindoles in good yield, via a novel addition–Claisen rearrangement sequence.

Methyllithium, in the presence of excess methyl iodide, can be used to convert suitably substituted aromatic bromides to the corresponding toluenes under mild conditions and in high yield.

Diesters obtained from diacids produced by oxidative ring cleavage of cycloadducts derived from acyl-nitroso compounds and cyclic 1,3-dienes undergo highly regioselective hydrolysis on reaction with lithium hydroperoxide, which allows for easy differentiation of the carboxyl groups leading to a new approach to polyoxamic acid.

An acyclic tricarbonyl(η 5 -trienyl)iron(1+) complex bearing an ester substituent at one terminus has been prepared from an η 4 -triene precursor complex in which the metalbound portion of the π-system separates alcohol and vinyl substituents. Reaction of the cation with nucleophiles affords σ,π-allyl products as well as the more normal η 4 -diene complexes.

Methyl 2,3,4-tri- O -acetyl- d -glucopyranuronate reacts with phenols under Mitsunobu conditions to give β-phenylglucuronides. Improved yields are obtained with p -methyl and p -methoxyphenol by prior complexation to the chromium tricarbonyl residue, which serves to increase the acidity of the phenol.

A synthesis of the enantiomer of nelarabine is described. Subtle changes in the protecting group strategy allow for an efficient inversion of the C-2′ stereocentre.

Three metabolites of N-[(1-butyl-4-piperidinyl)methyl]-3,4-dihydro-2H-[1,3]-oxazino[3,2_a]indole-10-carboxamide (SB-207266) (1) were synthesised and their pharmacological activity determined.

A number of aryl halides (X=Cl, Br, I) can be converted to the corresponding toluenes in an operationally simple manner using trimethylboroxine (TMB) as a partner for palladium-catalysed Suzuki–Miyaura coupling.

The phenoxyfurans (4) and (8) undergo a Diels–Alder reaction with dimethyl acetylenedicarboxylate (DMAD) to give the cycloadducts (5) and (9) which can be converted into the substituted diphenyl ethers (6) and (10) respectively.

The phenoxyfurans (4) and (8) undergo a Diels–Alder reaction with dimethyl acetylenedicarboxylate (DMAD) to give the cycloadducts (5) and (9) which can be converted into the substituted diphenyl ethers (6) and (10) respectively.

Methyl 2,3,4-tri- O -acetyl- d -glucopyranuronate reacts with phenols under Mitsunobu conditions to give β-phenylglucuronides. Improved yields are obtained with p -methyl and p -methoxyphenol by prior complexation to the chromium tricarbonyl residue, which serves to increase the acidity of the phenol.

When treated with potassium t-butoxide in dimethyl sulphoxide the chromium tricarbonyl complex of 3-(2-fluorophenyl)propan-1-ol underwent a rapid intramolecular nucleophilic substitution to give the corresponding complex of chroman, from which the heterocycle was obtained by oxidation with iodine. With metal alkoxides the chromium tricarbonyl complex of 2-(2-fluorophenyl)ethanol gave either mixtures (from which the product of intramolecular nucleophilic substitution was not isolated) or the products of intermolecular nucleophilic substitution.

Tricarbonyl(1,4-dichlorobenzene)chromium(O) and chlorobenzene(cyclopentadienyl)iron(II) hexaflurophosphate undergo nucleophilic substitution with sodium phenoxide to give tricarbonyl(4-chloro-1-phenoxybenzene)chromium(O) and phenoxybenzene(cyclopentadienyl)iron(II) hexaflurophosphate, respectively. In the former case, the second chlorine is subsequently displaced by methoxide, and this represents a potentially versatile synthesis of substituted diphenyl ethers. Neither of the complexes react with 2,6-dibromo-4-methylphenoxide, but both phenoxides add to substituted tricarbonylcyclohexadienyliumiron complexes to give neutral tricarbonyldieneiron(O) complexes.

L'addition de Diels Alder du butadiene-1,3 avec un naphtalene carbaldehyde conduit au squelette nor-19 podocarpene-12. On prepare une nor-19 podocarpene-13one-12 dont on etudie la structure cristalline. La lactonisation induite par l'iodure de trimethylsilane permet d'obtenir une nor-21 picrasanone-12 dont le noyau ABCD est precurseur des quassinoides

The displacement of the nitro group from substituted nitrobenzenes is used for the synthesis of diphenyl ethers. 1,4-Dinitrobenzene has been converted into a variety of hindered diphenyl ethers using 2,6-disubstituted phenoxides and studies show that the mechanism of formation of the ether (5a) is radical in nature.

1,4-Dichlorobenzene(tricarbonyl)chromium (I) undergoes consecutive nucleophilic substitution with sodium phenoxide (II) and methoxide (IV) to form the methoxyphenoxybenzene complex (V).

1,4-Dinitrobenzene undergoes nucleophilic substitution with sodium phenoxide and several hindered 2,6-substituted phenoxides to afford diphenyl ethers.

1,4-Dinitrobenzene undergoes nucleophilic substitution with sodium phenoxide and several hindered 2,6-substituted phenoxides to afford diphenyl ethers.

3-(o-Fluorophenyl)propan-1-ol can be cyclised readily to chroman either through chromium tricarbonyl complexes or (as also with substituted fluorophenylpropanols) by the action of the (η6-benzene)(η5-ethyltetramethylcyclopentadienyl)rhodium(III) cation.

The cyclisation of several 3-(2-fluorophenyl)-propanols to the corresponding chroman occurs in nitromethane–acetone solution at 80 °C when either the hexafluorophosphate (3) or tetrafluoroborate salt (4) of the (η5-ethyltetramethylcyclopentadienyl)(η6-benzene)rhodium(III) cation is used as a catalyst; the former salt is the more effective catalyst. The cyclisation is believed to involve the activation of the aryl fluoride (towards intramolecular nucleophilic substitution by the hydrpxy group) by the formation of a metal complex in which the aryl fluoride is π-bonded with the metal cation. It is suggested that the arene-exchange reaction which gives this π-bonded complex proceeds faster with the salt (3) than with the salt (4), and that this is the main factor for the greater efficiency of the former salt as a cyclisation catalyst.

The displacement of the nitro group from substituted nitrobenzenes is used for the synthesis of diphenyl ethers. 1,4-Dinitrobenzene has been converted into a variety of hindered diphenyl ethers using 2,6-disubstituted phenoxides and studies show that the mechanism of formation of the ether (5a) is radical in nature.