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Several novel thiazoles with side chains derived from natural amino acids and a dipeptide have been synthesised from N-protected α-amino glyoxals and cysteine.

N-Z-γ-amino alcohols derived from nonracemic β-amino acids are smoothly oxidised by manganese dioxide in acetonitrile to afford aldehydes which can be trapped in situ in Wittig reactions with carbonyl-substituted phosphoranes. The application of this methodology to the synthesis of the alkaloids (S)-(+)-N-BOC-coniie, (S)-(−)-coniceine and a pipecoline precursor is described.

Three rhenium(V) oxo phosphine complexes and methyltrioxorhenium have been used as catalysts for oxidation of sulfides to sulfoxides with urea-hydrogen peroxide as oxidant in acetonitrile; partial enantioselective oxidation of methylphenyl sulfide was observed with methyltrioxorhenium in the presence of a (+)-camphor derived pyrazine carboxylic acid.

Methyltrioxorhenium is an efficient catalyst for the oxidative ring opening of several substituted furans to enediones using urea hydrogen peroxide

A lipase-catalysed transesterification to effect a desymmetrisation has been used to produce chiral calix[4]arene derivatives with enantiomer excesses (ee) of up to 100%.

Several new chiral rhodium(II) catalysts have been synthesised for evaluation as catalysts in asymmetric oxonium ylide-[2,3] sigmatropic rearrangement of diazocarbonyl substrates; a catalyst derived from (S)-tert-leucine afforded a chiral benzofuranone derivative with an ee of 60 %.

The highest levels of enantiocontrol in intermolecular cyclopropanation reactions of methyl phenyldiazoacetate have been achieved with homochiral dirhodium(II) prolinates in pentane, the solvent effect for which (0.8 ± 0.2 kcal/mol) is associated with ligand alignment.

The fluorinated furanose unit of the anti-HIV-active nucleoside (2,3-dideoxy-2-fluoro-β- d - threo -pentofuranosyl)adenine, β-FddA, has been synthesized as its 5-trityl derivative with high stereocontrol from ( S )-trityl glycidol and phenylthioacetic acid.

Rhodium(II) catalysed decomposition of γ-alkoxy-α-diazo-β-ketoesters produce cis-2,5-disubstituted -3(2H)-furanones with high ( > 97%) stereoselectivity. The combination of a chiral auxiliary in the ester moiety of the diazo precursor and a chiral catalyst can lead to asymmetric synthesis with diastereoselectivities up to 61% de.

A new homochiral Rh(II) complex, Rh{HCO3}2{(+)-phos}2·5H2O, where (+)phosH represents (S)-(+)-1,1′-binaphthyl-2,2′-diyl hydrogen phosphate, has been prepared and used as a catalyst for reactions of diazocarbonyl compounds leading to enantioselective 2,3-sigmatropic rearrangement (first example), C H insertion and aromatic cycloaddition

New macrocyclic molecules are described containing two or three p-tert-butylcalix[4]arene subunits connected via their oxygen atoms. These macrocycles are available by two general methods which are capable of producing assemblies with bridges of varying rigidity and length.

Previously unreported N-Boc 4-nitropiperidine was prepared in two steps from N-Boc-piperidone. The synthetic utility of this new intermediate was demonstrated by the development of a new and simple route to spirolactam piperidines. Further synthetic work involving a challenging triazole cyclisation allowed the preparation of a spiropiperidine analogue of the eastern part of maraviroc.

The synthesis of the first expanded calixpyrrole: a calix[5]arene-capped calix[5]pyrrole 2 has been achieved using p-tert-butylcalix[5]arene pentamethyl ketone 1 as a template.

Tetraethyl- and tetrabutylammonium permanganate are less prone to explosive decomposition when heated than are benzyl(triethyl)ammonium and methyl-(triphenyl) phosphonium permanganate and are about equally effective as oxidants for the conversion of alkanes into alcohol and ketones.

Summary α-Chloroalkyl phenyl sulphides, derived from either the action of benzenesulphenyl chloride on α-diazoketones or of N-chlorosuccinimide on alkyl phenyl sulphides, are converted into phenylthioacetals on exposure to thiophenol in the presence of zinc chloride.

Cyclic α-diazoketones react with phenylsulphenyl chloride at room temperature to furnish α-chloro-α-(phenylthio)cycloalkanones which undergo ready dehydrochlorination to α-(phenylthio)cycloalkenones when treated with triethylamine; acyclic, terminal α-diazoketones also furnish α-chloro-α-(phenylthio)adducts which are useful electrophiles in the synthesis of α-phenyl-α-(phenylthio)ketones.

αα-Addition of thiophenol to α-diazoketones is catalysed efficiently by rhodium(II) acetate in benzene solution at room temperature, offering a convenient regio-specific route to a variety of α-(phenylthio)ketones.

Summary Aromatic γ-lactones can be synthesised from 4-substituted phenols in a single step by zinc chloride-catalysed alkylation with methyl-2-chloro-2-(butylthio or phenylthio)propionate or acetate.

Alkenyl tosylates of the type RCHCH(CH 2 ) n OTs [RH, n=9; RH, n=7; and RCH 3 (CH 2 ) 7 , n=8] undergo metathesis using a WCl 6 -Me 3 SnCl catalyst system, producing difunctionalised alkenes of the type TsO(CH 2 ) n CHCH(CH 2 ) n OTs (n=7,8, and 9); examples of the use of these products in synthesis are presented.