Abstract: Aziridines may be subjeted to a cyclooligomerization reaction to produce polyazacycloalkane compounds useful for example in the preparation of chelating agents for use in diagnostic imaging contrast agents. N-benzyl-aziridine in particular is useful as it can be cyclotetramerized and debenzylated to yield cyclen, a key intermediate in chelating agent preparation. The invention provides a particularly attractive route to production of N-benzyl and other N-arylmethyl aziridines of formula (I) where each R1 is independently hydrogen or a group AR and Ar is an optionally substituted phenyl group. The process comprises reacting a purified N-arylmethylethanolamine-sulphonate sulphonate ester with a base. N-aryimethyl-ethanolamine sulphonate ester of the formula R′NHCH2CH2OSO3H, wherein the N-arylmethyl group R′ is an N-(bisarylmethyl) or N-(triarylmethyl) group, as intermediates.

Abstract: 5-Substituted isophthalic acid bis(allylamides) and bis(allylamide epoxides) in which said 5-substituent is --NO.sub.2, --NH.sub.2, --NHR.sup.1 or --NR.sup.1 R.sup.2 where R.sup.1 and R.sup.2 are independently optionally substituted alkyl, alkenyl, acyl, aryl, aralkyl or alkaryl groups.

Abstract: Aziridines may be subjected to a cyclooligomerization reaction to produce polyazacycloalkane compounds useful for example in the preparation of chelating agents for use in diagnostic imaging contrast agents. N-benzyl-aziridine in particular is useful as it can be cyclotetramerized and debenzylated to yield cyclen, a key intermediate in chelating agent preparation. The invention provides a particularly attractive route to production of N-benzyl and other N-arylmethyl aziridines of formula (I) where each R.sub.1 is independently hydrogen or a group AR and Ar is an optionally substituted phenyl group. The process comprises reacting a purified N-arylmethylethanolaminesulphonate ester with a base. N-arylmethyl-ethanolamine sulphonate ester of the formula R'NHCH.sub.2 CH.sub.2 OSO.sub.3 H, wherein the N-arylmethyl group R' is an N-(bisarylmethyl) or N-(triarylmethyl) group, as intermediates. In a further aspect, the invention provides compounds of formula (II) ##STR1## where Ar and R.sub.

Abstract: The invention provides a process for the production of a 2,3-dihydroxypropylamino compound, said process comprising the reaction steps of:(i) obtaining an allylamino compound;(ii) epoxidizing said allylamino compound to yield an epoxypropylamino compound; and(iii) hydrolysing said epoxypropylamino compound to yield a 2,3-dihydroxypropylamino compound.This process may be used to produce simple 2,3-dihydroxypropylamino compounds such as APD or complex ones such as BAPD (an intermediate in the production of iohexol).

Abstract: The present invention provides a synthetic route for tetraazacycloalkane preparation which facilitates heteropoly-N-alkylation of the macrocyclic product, and is thereby beneficial for the production of chelating agents and chelates useful in diagnostic imaging. The process involves (i) reacting a tetraazaalkane with a bridging agent to couple four amine nitrogens of said tetraazaalkane to a bridging moiety to yield a fused tricyclic intermediate, (ii) reacting said intermediate to introduce an alkylene bridge between the secondary amine nitrogens in the outer rings of the fused tricyclic intermediate, optionally by decoupling an alkanediylidene bridging moiety from the tertiary amine nitrogens at the ring fusion sites of the fused tricyclic intermediate, and (iii) where necessary, decoupling said bridging moiety to yield a macrocyclic tetraazacycloalkane.

Abstract: This invention is a process for the production of H.sub.2 O.sub.2 using fullerene. The process involves the hydrogenation of the fullerenes and the reaction of the hydrogenated fullerenes with O.sub.2 to produce H.sub.2 O.sub.2. Preferably the process utilizes a two-phase reaction mixture of a solvent and water. The solvent solvates the fullerenes and any applicable hydrogenation catalyst. The H.sub.2 O.sub.2 is extracted into the water phase for removal from the process.

Abstract: The additional of redox-active metal components and ligands, alternatively or simultaneously, results in increased conversion and selectivity in the palladium-catalyzed oxidation of olefins to carbonyl products in the presence of polyoxoanions. In preferred modes, heteropolyoxoanions and Isopolyoxoanions containing tungsten, molybdenum and vanadium, individually or in combination, are described. The use of copper as the redox-active metal component shows reduced allylic reactivity. The elimination of chloride from the catalyst system provides substantial engineering advantages over the prior art, particularly, the reduction of corrosion and chloro-organic by-product formation. The use of redox-active metal components and/or ligands makes the palladium-polyoxoanion catalyst system industrially practicable.

Abstract: A substantially chloride-free palladium oxidation system, comprising a palladium component, a copper component, and a ligand is described. The Wacker system, consisting of palladium and copper chlorides is also improved by the addition of a ligand. The palladium and copper counterion are independently selected from BF.sub.4.sup.--, CF.sub.3 COO.sup.--, CH.sub.3 COO.sup.--, SO.sub.4.sup..dbd., and NO.sub.3.sup.--. The ligand is preferably a nitrile-containing compound.

Abstract: A substantially chloride-free palladium oxidation system, comprising a palladium component, a copper component, and a ligand is described. The Wacker system, consisting of palladium and copper chlorides is also improved by the addition of a ligand. The palladium and copper counterion are independently selected from BF.sub.4.sup.-, CF.sub.3 COO.sup.-, SO.sub.4.sup.=, and NO.sub.3.sup.-. The ligand is preferably a nitrile-containing compound.

Abstract: The addition of redox-active metal components and ligands, alternatively or simultaneously, results in increased conversion and selectivity in the palladium-catalyzed oxidation of olefins to carbonyl products in the presence of polyoxoanions. In preferred modes, heteropolyoxoanions and isopolyoxoanions containing tungsten, molybdenum and vanadium, individually or in combination, are described. The use of copper as the redox-active metal component shows reduced allylic reactivity. The elimination of chloride from the catalyst system provides substantial engineering advantages over the prior art, particularly, the reduction of corrosion and chloro-organic by-product formation. The use of redox-active metal components and/or ligands makes the palladium-polyoxoanion catalyst system industrially practicable.

Abstract: The addition of redox-active metal components and ligands, alternatively or simultaneously, results in increased conversion and selectivity in the palladium-catalyzed oxidation of olefins to carbonyl products in the presence of polyoxoanions. In preferred modes, heteropolyoxoanions and isopolyoxoanions containing tungsten, molybdenum and vanadium, individually or in combination, are described. The use of copper as the redox-active metal component shows reduced allylic reactivity. The elimination of chloride from the catalyst system provides substantial engineering advantages over the prior art, particularly, the reduction of corrosion and chloro-organic by-product formation. The use of redox-active metal components and/or ligands makes the palladium-polyoxoanion catalyst system industrially practicable.

Abstract: A procedure for the synthesis of biotin is disclosed whereby unsaturated diacylated biotin precursors are catalytically hydrogenated with the substantial absence of sulfur poisoning. The hydrogenation procedure dislcosed herein results in optically pure biotin.

Abstract: Corrosion of corrodible metal material is prevented by contacting the material with an effective amount of a macrocyclic tetramine.