Christopher R. A. Godfrey

Observations on the chemistry of the iodoxy group

Abstract In the presence of an appropriate catalyst, iodoxy-arenes act as oxidants towards a variety of diverse functional groups

A novel entry to carbenoid species viaβ-ketosulfoxonium ylides

In the presence of suitable rhodium(II) catalysts, lactam derived β-ketosulfoxonium ylides can be transformed to β-oxonitrogen heterocycles, e.g. substituted 4-oxopyrrolidine, viaintermediates of carbenoid nature.

The stereospecific synthesis of (2S,3R) 3-carboxyproline and (2S,3R) 3-aminoproline

Abstract Stereospecific syntheses of (2 S ,3 R ) 3-carboxyproline and (2 S ,3 R ) 3-aminoproline are reported which make use of the stereospecific alkylation of (4 S )- N -( t -butyldimethylsilyl)azetidin-2-one 4-carboxylic acid with the cyclic sulfate derived from ethylene glycol.

Stereospecific Synthesis of Chlamydocin

Abstract A stereospecific synthesis of the cyclic tetrapeptide chlamydocin via free radical homologation from a ( S )-2-amino-5-iodopentanoic acid containing cyclic tetrapeptide is described.

A novel route to unsymmetrical stilbene derivatives via intramolecular free radical ipso substitution reactions

Unsymmetrical stilbene derivatives can be prepared via intramolecular free radical ipso substitution reactions using suitably constituted vinyl sulfonate and sulfonamide tethering chains.

A practical catalytic method for the preparation of steroidal 1,4-dien-3-ones by oxygen atom transfer from iodoxybenzene to diphenyl diselenide

The dehydrogenation of steroidal 3-ketones can be accomplished in high yield using benzeneseleninic anhydride generated in situ by efficient oxygen atom transfer from iodoxybenzene to catalytic amounts of diphenyl diselenide. An experimentally convenient and economical development of this catalytic cycle is the use of meta-iodoxybenzoic acid which both avoids chromatography and allows recovery of meta-iodobenzoic acid and diphenyl diselenide. 12-Hydroxy- and 12-keto-steroids are also dehydrogenerated very efficiently using this catalytic process.

Dissolving metal reduction of esters to alkanes. A method for the deoxygenation of alcohols

Diverse carboxylic esters have been reduced with dissolving Group 1A metals. Using lithium in ethylamine, sterically hindered esters (RCO2R′) were deoxygenated giving the alkane (R′H) whereas non-hindered esters regenerated the parent alcohol (R′OH). This permitted the selective deoxygenation of diesters. Conversely, potassium–sodium eutectic solubilised with 18-crown-6 in t-butylamine and tetrahydrofuran (THF) efficiently deoxygenated both hindered and non-hindered esters. In the absence of nucleophiles at ambient temperature the principal reaction of carboxylic ester radical anions was deoxygenation.

A new homolytic method for the stereospecific synthesis of (2S,9S)-2-amino-8-oxo-9,10-epoxydecanoic acid in protected form

(2S,9S)-2-Amino-8-oxo-9,10-epoxydecanoic acid 1, (AOE), has been synthesized in protected form by homolytic homologation from protected (S)-2-amino-5-iodopentanoic acid.

Formal Synthesis of AB3217-Afrom Anisomycin Using a Directed Benzylic Oxidation

A formal synthesis of the insecticidal natural product AB3217-A involving an unusual diastereoselective benzylic oxidation is described.