Ian A. O'Neil

DPPE: A convenient replacement for triphynylphosphine in the staudinger and Mitsunobu reactions

Abstract DPPE has been shown to replace triphenylphosphine in the Staudinger and Mitsunobu reactions. The resulting bis(phosphine oxide) by-product is readily removed allowing for rapid and simple purification of the reaction mixture.

The synthesis of functionalised β-hydroxyhydroxylamines via the ring opening of epoxides and their use in reverse Cope cyclisations

Abstract Functionalised epoxides have been found to undergo high yielding and regioselective ring opening with hydroxylamines in methanol to give β-hydroxyhydroxylamines. Suitable substrates were found to undergo a reverse Cope cyclisation on heating in CHCl 3 to give functionalised piperidine N -oxides.

A convenient synthesis of secondary hydroxylamines

Abstract The oxidation of a range of β-cyanoethyl tertiary amines with m CPBA gives the corresponding N -oxides, which can be isolated or undergo Cope-elimination to give secondary hydroxylamines in excellent yield.

THE SYNTHESIS OF A NOVEL BENZODIAZOCINE VIA AN INTRAMOLECULAR STAUDINGER/AZA-WITTIG CYCLIZATION

Abstract The novel pyrrolobenzodiazocine (1) has been prepared by an intramolecular Staudinger/aza Wittig protocol from the precursor azido aldehyde (2) in a remarkable 93% yield. Aldehyde (2) was prepared by coupling protected homoprolinol with 2-azidobenzoic acid followed by deprotection and oxidation.

The stereospecific addition of hydroxylamines to α,β-unsaturated sulfones, nitriles and nitro compounds

Abstract N -Alkyl hydroxylamines have been shown to undergo a highly stereospecific cis addition to α,β-unsaturated sulfones, nitriles and nitro compounds.

The preparation of epoxy isonitriles (isocyanooxiranes)

Abstract The preparation of epoxy isonitriles from vinyl formamides using an epoxidation dehydration sequence is described.

The synthesis of β-N-tosylamino hydroxylamines via the ring opening of N-tosylaziridines and their use in reverse Cope cyclisations

Abstract N -Tosylated aziridines have been found to undergo high yielding and regioselective ring opening with hydroxylamines in diethyl ether in the presence of boron trifluoride diethyl ether complex to give β- N -tosylamino hydroxylamines. Suitable substrates were shown to undergo reverse-Cope cyclisations to give amino functionalised pyrrolidine and piperidine N -oxides.

Sunthesis of functionalised 2′-C-branched nucleosides via their γ-butyrolactones

Abstract Functionalised 2′-C-branched nucleosides that contain either a carboxylic acid (2), a primary amide (3) or a primary hydroxyl (4) group have been prepared and their protection for oligonucleotide synthesis investigated. The 2′-C-3′-O-γ-butyrolactone (5) was also shown to be a useful intermediate for the preparation of these analogues.

The ring opening of aziridine-2-carboxylate esters with organometallic reagents

The ring opening of aziridines with organocuprate reagents provides a new entry to amino acids.

The synthesis of 2′-homouridine, its incorporation into a dinucleoside monophosphate and hydrolytic behaviour of the dimer

Abstract An efficient route to 2′-homouridine ( 1 ), a new nucleoside analogue, is reported that is based on an ene reaction. This nucleoside has been incorporated into a dinucleoside monophosphate and hydrolytic studies on the dimer show that it does not behave like a ribonucleotide.