Colin R. McArthur

Synthesis, electrochemical and spectroelectrochemical studies of metal-free 2,9,16,23-tetraferrocenylphthalocyanine

Abstract Cyclic voltammetric, differential pulse voltammetric and spectroelectrochemical methods have been used to study the newly synthesized metal-free 2,9,16,23-tetraferrocenylphthalocyanine in dichloroethane. Two reversible reduction peaks are obtained, corresponding to electrode reactions of the phthalocyanine ring. The multiple ferrocenyl redox centers are oxidized at one potential. The electronic spectra are reported for this species in different oxidation states.

Amino Group Blocking. Improved Method for N-Phthaloylation Using N-(Ethoxycarbonyl)phthalimide

Abstract N-Phthaloylation, as a means of protecting primary amino groups, especially in the synthesis of peptides, has been known for some time.1 That N-phthaloylamines generally are easily crystallized, and that the phthaloyl group can readily be removed by hydrazinolysis or phenylhydrazinolysis have been recognized advantages in using this approach for the protection of amino groups during syntheses.1,2,3 The reaction of phthalic anhydride

The Asymmetric Synthesis of 4,4-Dimethyl-3-Substitutedbutyrolactones

Abstract Chiral 4,4-dimethyl-3-phenyl and 3-(3-oxobutyl)butyrolactones have been prepared in high enantiomeric excesses by a mild acid catalysed cleavage and lactonisation of the Michael adducts obtained from asymmetric additions of isopropenyl magnesium bromide to α,β-unsaturated carboxylic amides derived from 1-ephedrine.

Asymmetric induction in the cycloaddition of 1,3-butadiene to a polymer-bound chiral acrylate

Crosslinked polystyrene resins containing pendant benzyl acrylate or chiral acrylates derived from R-(−)-1,3-butanedoil reacted with 1,3-butadiene or 2,3-dimethyl-1,3-butadiene in the presence of the Lewis acid catalysts TiCl4, TiCl3(OiPr), or TiCl2(OiPr)2 to yield Diels-Alder adducts. Cleavage of the adducts gave racemic or optically active 3-cyclohexen-1-ylmethanol and 3,4-dimethyl-3-cyclohexen-1-ylmethanol. The polymerbound Diels-Alder reactions were compared with their analogous reactions in solution. In reactions leading to optically active products the enantiomeric excesses on the polymer were at least as high as those performed in solution.