Jennifer A. Kenny

Rhodium versus ruthenium: contrasting behaviour in the asymmetric transfer hydrogenation of α-substituted acetophenones

Abstract The reduction of a number of α-substituted acetophenones has been achieved using both ruthenium(II)- and rhodium(III)-based asymmetric transfer hydrogenation catalysts employing formic acid as the hydrogen donor.

Novel catalysts for asymmetric reduction of carbonyl groups

The use of (i) enantiomerically pure phosphinamides coupled to borane and (ii) an enantiomerically pure amino alcohol coupled to a transfer hydrogenation process, in the asymmetric catalysis of the reduction of ketones to alcohols, is described. The former process is particularly suited to the reduction of alpha-chlorinated substrates, affording e.e.s of up to 94%, whilst the latter process is optimal for unfunctionalised ketones, affording e.e.s of up to 98%.

Recent developments in the area of asymmetric transfer hydrogenation

The use of an enantiomerically pure amino alcohol, coupled to a transfer hydrogenation process, in the asymmetric catalysis of the reduction of ketones to alcohols, is described. The process works well for unfunctionalised ketones, affording e.e.s of up to 98%, and excellent conversions. We have recently extended, for the first time in this application, the scope of the methodology to the reductions of a-heteroatom substituted substrates, through the use of the appropriate protecting groups on each atom.

Asymmetric transfer hydrogenation of ketones using amino alcohol and monotosylated diamine derivatives of indane

A series of 1,2-amino alcohol and 1,2-monotosylated diamine derivatives of indane have been applied as ligands in the asymmetric ruthenium(II)-catalysed transfer hydrogenation reaction of a series of ketones. Of these, the cis-1-aminoindan-2-ol derivative gives some of the highest asymmetric inductions reported for any amino alcohol ligand in this application.

The detection of intermediates in the ruthenium(II) catalysed asymmetric hydrogenation of ketones using electrospray ionisation mass spectrometry

The use of electrospray ionisation mass spectrometry for the detection of the intermediate species involved in the ruthenium(II)/amino alcohol reduction of ketones to alcohols is described.

SYNTHESIS AND ELECTROSPRAY MASS SPECTROMETRIC STUDIES ON A CHIRAL, NON-RACEMIC, PHOSPHORAMIDE RECEPTOR MOLECULE

Abstract The synthesis of a class of macrocyclic receptors containing a phosphoramide is described. The preliminary evaluation of this new receptor for interactions with several homochiral amines using electrospray ionisation mass spectrometry is also described.