Warwick Raverty | Monash University (original) (raw)

Papers by Warwick Raverty

Journal of the Chemical Society, 1977

Page 1. 1204 I 1 JCS Perkin I lllllll Metabolites from the Sponge Pachymatisma johnstoni; L-6-Bro... more Page 1. 1204 I 1 JCS Perkin I lllllll Metabolites from the Sponge Pachymatisma johnstoni; L-6-Bromo-hypaphorine, a New Amino-acid (and its Crystal Structure) By Warwick D. Raverty and Ronald H. Thornson," Department ...

... Cai, Jackie; Clark, Noel and Raverty, Warwick. New Peroxide Activators for Kraft Pulp Bleachi... more ... Cai, Jackie; Clark, Noel and Raverty, Warwick. New Peroxide Activators for Kraft Pulp Bleaching [online]. In: Appita Conference and Exhibition (63rd : 2009 : Melbourne, Vic.). 63rd Appita Annual Conference and Exhibition, Melbourne 19-22 April 2009. Carlton, Vic.: Appita Inc ...

Fibers and Polymers, Jun 1, 2005

Paper T he present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (P... more Paper T he present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibres had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

Journal of Organic Chemistry, Nov 8, 2017

Levoglucosenone (LGO) is the major product formed when cellulose is pyrolyzed in the presence of ... more Levoglucosenone (LGO) is the major product formed when cellulose is pyrolyzed in the presence of acid at temperatures between 170-350 °C. The current intense interest in biomass conversion has led to a number of reports on its preparation, however, there is still uncertainty on the mechanism leading to LGO. We propose a new mechanism which involves a C2-C1 hydride shift followed by intramolecular trapping of a dioxyallyl cation. The reaction has been modelled using DFT calculations from the known LGO precursors, levoglucosan and 1,4:3,6-dianhydroglucose to a common intermediate with calculated barriers of 10.6 and 13.5 kcal.mol-1 respectively. A discussion of the literature on the formation of LGO from late pathway intermediates is also provided.

59th Appita Annual …, 2005

... Text PDF (1357kb). To cite this article: Wedding, Michael J; Helmer, Richard JN; Raverty, War... more ... Text PDF (1357kb). To cite this article: Wedding, Michael J; Helmer, Richard JN; Raverty, Warwick D; Clark, Noel B; Irvine ... Carlton, Vic.: Appita Inc., 2005: 1-6. Availability: <http://search.informit. com.au/documentSummary;dn=338983367123463;res=IELHSS> ISBN: 0958554897. ...

Appita …, 2001

... wire, and v = viewer). The key wet-end features of the UoM include: a velocity profile above ... more ... wire, and v = viewer). The key wet-end features of the UoM include: a velocity profile above the wire, similar suspension characteristics, (similar consistency range and depth), and a similar pressure profile. The stationary wire ...

57th Appita Annual …, 2003

... PDF (483kb). To cite this article: Helmer, Richard JN; Irvine, Geoffrey M; Raverty, Warwick D... more ... PDF (483kb). To cite this article: Helmer, Richard JN; Irvine, Geoffrey M; Raverty, Warwick D; Vanderhoek, Nafty; Clark, Noel and Covey ... Carlton, Vic.: Appita Inc., 2003: 1-9. Availability: <http://search.informit.com.au/documentSummary;dn=079519242353028;res=IELHSS> ISBN ...

Tetrahedron, 1981

ABSTRACT The concept is discussed of superimposed lateral control of reactivity, stereochemistry ... more ABSTRACT The concept is discussed of superimposed lateral control of reactivity, stereochemistry and structures, by attachment of complexed metal atoms to olefinic systems. This differs from classical endogenous control of synthesis by classical anionoid and cationoid groups in the skeleton, and its application has many theoretical and practical advantages. It is illustrated by considerations of reactions of substituted tricarbonylcyclohexa-l,3-dieneiron derivatives; notably the derived dienyliron salts, which are defined as equivalents of specifically substituted aryl cations or as cyclohex-2-enone cations, dependent on the structures and reaction sequences. The effects are noted of classical substituents on the positions and on the rates of reactivity of some complexed dienyl cations ; both regio- and stereospecificities are dependent on the nature of the anion involved and the conditions. Probable mechanisms are discussed. Other effects of lateral control include those on the classical reactivities of attached groups (such as hydrolysis of CO2Me) and on adjacent groups, such as stereochemistry of reduction of the 3-carbonyl in the ergosterone complex. Some useful new C-C bond-forming reactions made possible by the approach are noted.

Australian Journal of Chemistry, 1976

The major polycyclic constituent of an asterolecaniid Callococcus acaciae (Maskell) is shown to b... more The major polycyclic constituent of an asterolecaniid Callococcus acaciae (Maskell) is shown to be the 10,l0'-dimer of acetylemodin anthrone glucoside. This follows from hydrolytic, reductive andoxidative reactions. The coccid Cryptes baccatum Maskell is shown to contain ceroalbolinic acid as its principal colouring matter. On decarboxylation it gave isoerythrolaccin, identical with a syntheticspecimen

Australian Journal of Chemistry, 1978

The anthraquinone emodin (9) was rapidly and efficiently converted into catenarin (13) by treatme... more The anthraquinone emodin (9) was rapidly and efficiently converted into catenarin (13) by treatment with a mixture of oleum and boric acid at room temperature. Chrysophanol (15) similarly gave islandicin (16), while related anthraquinones were hydroxylated in essentially the same way, though none as rapidly as emodin. The specificity of such processes is synthetically useful in generally involving substitution of the less highly hydroxylated ring. This is in contrast to hydroxylation with persulfate in sulfuric acid which, for emodin, occurred chiefly in the more highly hydroxylated ring, as did sulfonation.

Tetrahedron Letters, 1980

Asyreaetric coordination of prochiral 1,3-dienes to form optically active (dienejFe(CC03 complexe... more Asyreaetric coordination of prochiral 1,3-dienes to form optically active (dienejFe(CC03 complexes has been achieved by direct transfer of the Fe02012 group from chiral enone complexes. Complexation of an unsymmetrically substituted 1,3-diene produces a chiral molecule, with one face of the diene distinguished by bonding to the metal. Were we report a complexation process which enables the two faces of a prochiral diene to be differentiated for the first time, resulting in the production of optically active tricarbonyliron complexes. Various a,B-unsaturated ketones, which form moderately stable tricarbonyliron complexes, are known to act as a convenient source of an iron carbonyl moiety for transfer to 1,3-dienes.l Analogous transfer reagents prepared simply from two readily available chiral enones, (+)-pulegone (I) and (-)-3B-acetyloxypregna-5,16-diene-lo-one (II), (16-DHA) were used without isolation to provide a direct synthesis of optically active complexes of 1-methoxycyclohexa-1,3-diene (III), 1-methoxy-4-methylcyclohexa-1,3-diene (IV) and methyl sorbate (V), as shown in the Table. Complexes of pulegone3 were prepared thermally from Fe2(CO)S (light petroleum, b.p. 40-60°, 5 hrs). After filtration through celite , evaporation of solvent and Fe(C0)5, addition of the 1,3-diene in degassed benzene, toluene or light petroleum (b.p. 40-60') and heating at reflux for the appropriate time, the crude product was distilled and chromatographed on silica gel. The compounds were distilled a second time and optical rotations measured on analytically pure samples. A similar method was used for 3@acetyloxypregna-5,16-diene-ZO-one, except that crystallisation of the crude product from hexane resulted in

Chemischer Informationsdienst, Apr 15, 1980

Chemischer Informationsdienst, Nov 16, 1982

Die Estergruppe in den Cyclohexadienen (Ia) und (Ib) begünstigt die stereoselektive Komplexbildun... more Die Estergruppe in den Cyclohexadienen (Ia) und (Ib) begünstigt die stereoselektive Komplexbildung der β‐Isomeren (IIa) (dominierende Komponente im trennbaren Gemisch mit (IIIa) und (IVa); Gesamtausb.

Polymer-plastics Technology and Engineering, Jul 10, 2007

... Alireza Ashori a * & Warwick D. Raverty b pages 683-687. ... [Web of Science ®] View all ... more ... Alireza Ashori a * & Warwick D. Raverty b pages 683-687. ... [Web of Science ®] View all references 4 4. Ashori , A. ; Jalaluddin , H. ; Wan , Md. ; Zin , WY ; Mohd Nor , MY 2006 . Polymer-Plastics Technology and Engineering Journal 2006 , 45 ( 1 ), 125 – 129 . ...

Frontiers research topics, 2020

Lignocellulose is the only renewable carbon source that can help replace oil-based chemicals and ... more Lignocellulose is the only renewable carbon source that can help replace oil-based chemicals and materials, in the process fighting global warming. However, because of its chemical and structural complexity, lignocellulose transformation into advanced products requires a better understanding of its composition and of its architecture at different scales, as well as a combination of physical, biological, and chemical processes, in order to render this transformation efficient and economically competitive. Tremendous efforts continue to be made toward the production of ethanol as a biofuel from various lignocellulosic feedstocks. Furthermore, recent successes have been achieved in extracting fibers to prepare composite materials that can compete with plastic fabrics. Importantly, lignocellulose chemistry can bring to the market original and complex chemicals that can lead to new applications, in particular when exploiting aromatic molecules or oligosaccharides from lignocellulose to produce solvents, surfactants, plasticizers, functional additives for food/feed/cosmetics, drugs, monomers, and polymers. In addition to this broad range of molecular products, fibers and particles fractionated from the lignocellulosic biomass are increasingly used to elaborate bio-based composite materials

Australian Journal of Chemistry, 1978

Pigments of the Australian lacciferid, Austrotachardia acaciae Maskell, differ from those of Indi... more Pigments of the Australian lacciferid, Austrotachardia acaciae Maskell, differ from those of Indian lac insects in that the major constituent is xantholaccaic acid B (9) rather than a mixture of laccaic acids. Its structure has been determined by single-crystal X-ray diffraction of a new hexamethyl derivative. Xantholaccaic acids have not previously been found in nature. Earlier parts of this series have examined species from within the coccoid families Asterolecaniidae, Coccidae, Eriococcidae and ~seudococcidae.' All contained polyketide anthraquinones or related systems. This paper is concerned with a further family, Lacciferidae, exemplified by the species Austrotachardia acaciae aske ell.^'^ This ranges over the dry inland areas of Australia, parasitizing mulga and allied species of Acacia. It is related to the Indian lac insect Laccifer lacca Kerr, the source of lac dyestuffs and of shellac? The lac pigments have been studied by Sch~field,~ V e n k a t a r a m a~~~'~ and their coworkers. They include deoxyerythrolaccin (l), erythrolaccin (2), isoerythrolaccin (3) and laccaic acid D (4), and a complex series of polar laccaic acids A, B, C and E, formulated as (5), (6), (7) and (8) respectively. Because of their complexity structures (5)-(8) have not been confirmed by synthesis or degradation to known products. Samples of A. acaciae were taken from several different hosts at widely separated localities in Western Australia. Both living and degenerate specimens were examined. A11 afforded qualitatively similar mixtures of pigments but the best yields were obtained from living insects. Intractable, presumably polymeric, materials appeared to develop with aging. As in the case of L. lacca the mature insects were embedded in very large quantities of their own exuded resin. The components of this resin ranged widely in polarity,

Chemischer Informationsdienst, Jun 1, 1982

Reaktionen an zahlreichen Tricarbonyl‐n‐cyclohexadien‐eisen(0)‐Komplexen werden unter Berücksicht... more Reaktionen an zahlreichen Tricarbonyl‐n‐cyclohexadien‐eisen(0)‐Komplexen werden unter Berücksichtigung sterischer Gegebenheiten untersucht.

Chemischer Informationsdienst, Nov 16, 1982

Chemischer Informationsdienst, Mar 27, 1979

Journal of the Chemical Society, 1977

Page 1. 1204 I 1 JCS Perkin I lllllll Metabolites from the Sponge Pachymatisma johnstoni; L-6-Bro... more Page 1. 1204 I 1 JCS Perkin I lllllll Metabolites from the Sponge Pachymatisma johnstoni; L-6-Bromo-hypaphorine, a New Amino-acid (and its Crystal Structure) By Warwick D. Raverty and Ronald H. Thornson," Department ...

... Cai, Jackie; Clark, Noel and Raverty, Warwick. New Peroxide Activators for Kraft Pulp Bleachi... more ... Cai, Jackie; Clark, Noel and Raverty, Warwick. New Peroxide Activators for Kraft Pulp Bleaching [online]. In: Appita Conference and Exhibition (63rd : 2009 : Melbourne, Vic.). 63rd Appita Annual Conference and Exhibition, Melbourne 19-22 April 2009. Carlton, Vic.: Appita Inc ...

Fibers and Polymers, Jun 1, 2005

Paper T he present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (P... more Paper T he present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibres had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

Journal of Organic Chemistry, Nov 8, 2017

Levoglucosenone (LGO) is the major product formed when cellulose is pyrolyzed in the presence of ... more Levoglucosenone (LGO) is the major product formed when cellulose is pyrolyzed in the presence of acid at temperatures between 170-350 °C. The current intense interest in biomass conversion has led to a number of reports on its preparation, however, there is still uncertainty on the mechanism leading to LGO. We propose a new mechanism which involves a C2-C1 hydride shift followed by intramolecular trapping of a dioxyallyl cation. The reaction has been modelled using DFT calculations from the known LGO precursors, levoglucosan and 1,4:3,6-dianhydroglucose to a common intermediate with calculated barriers of 10.6 and 13.5 kcal.mol-1 respectively. A discussion of the literature on the formation of LGO from late pathway intermediates is also provided.

59th Appita Annual …, 2005

... Text PDF (1357kb). To cite this article: Wedding, Michael J; Helmer, Richard JN; Raverty, War... more ... Text PDF (1357kb). To cite this article: Wedding, Michael J; Helmer, Richard JN; Raverty, Warwick D; Clark, Noel B; Irvine ... Carlton, Vic.: Appita Inc., 2005: 1-6. Availability: <http://search.informit. com.au/documentSummary;dn=338983367123463;res=IELHSS> ISBN: 0958554897. ...

Appita …, 2001

... wire, and v = viewer). The key wet-end features of the UoM include: a velocity profile above ... more ... wire, and v = viewer). The key wet-end features of the UoM include: a velocity profile above the wire, similar suspension characteristics, (similar consistency range and depth), and a similar pressure profile. The stationary wire ...

57th Appita Annual …, 2003

... PDF (483kb). To cite this article: Helmer, Richard JN; Irvine, Geoffrey M; Raverty, Warwick D... more ... PDF (483kb). To cite this article: Helmer, Richard JN; Irvine, Geoffrey M; Raverty, Warwick D; Vanderhoek, Nafty; Clark, Noel and Covey ... Carlton, Vic.: Appita Inc., 2003: 1-9. Availability: <http://search.informit.com.au/documentSummary;dn=079519242353028;res=IELHSS> ISBN ...

Tetrahedron, 1981

ABSTRACT The concept is discussed of superimposed lateral control of reactivity, stereochemistry ... more ABSTRACT The concept is discussed of superimposed lateral control of reactivity, stereochemistry and structures, by attachment of complexed metal atoms to olefinic systems. This differs from classical endogenous control of synthesis by classical anionoid and cationoid groups in the skeleton, and its application has many theoretical and practical advantages. It is illustrated by considerations of reactions of substituted tricarbonylcyclohexa-l,3-dieneiron derivatives; notably the derived dienyliron salts, which are defined as equivalents of specifically substituted aryl cations or as cyclohex-2-enone cations, dependent on the structures and reaction sequences. The effects are noted of classical substituents on the positions and on the rates of reactivity of some complexed dienyl cations ; both regio- and stereospecificities are dependent on the nature of the anion involved and the conditions. Probable mechanisms are discussed. Other effects of lateral control include those on the classical reactivities of attached groups (such as hydrolysis of CO2Me) and on adjacent groups, such as stereochemistry of reduction of the 3-carbonyl in the ergosterone complex. Some useful new C-C bond-forming reactions made possible by the approach are noted.

Australian Journal of Chemistry, 1976

The major polycyclic constituent of an asterolecaniid Callococcus acaciae (Maskell) is shown to b... more The major polycyclic constituent of an asterolecaniid Callococcus acaciae (Maskell) is shown to be the 10,l0'-dimer of acetylemodin anthrone glucoside. This follows from hydrolytic, reductive andoxidative reactions. The coccid Cryptes baccatum Maskell is shown to contain ceroalbolinic acid as its principal colouring matter. On decarboxylation it gave isoerythrolaccin, identical with a syntheticspecimen

Australian Journal of Chemistry, 1978

The anthraquinone emodin (9) was rapidly and efficiently converted into catenarin (13) by treatme... more The anthraquinone emodin (9) was rapidly and efficiently converted into catenarin (13) by treatment with a mixture of oleum and boric acid at room temperature. Chrysophanol (15) similarly gave islandicin (16), while related anthraquinones were hydroxylated in essentially the same way, though none as rapidly as emodin. The specificity of such processes is synthetically useful in generally involving substitution of the less highly hydroxylated ring. This is in contrast to hydroxylation with persulfate in sulfuric acid which, for emodin, occurred chiefly in the more highly hydroxylated ring, as did sulfonation.

Tetrahedron Letters, 1980

Asyreaetric coordination of prochiral 1,3-dienes to form optically active (dienejFe(CC03 complexe... more Asyreaetric coordination of prochiral 1,3-dienes to form optically active (dienejFe(CC03 complexes has been achieved by direct transfer of the Fe02012 group from chiral enone complexes. Complexation of an unsymmetrically substituted 1,3-diene produces a chiral molecule, with one face of the diene distinguished by bonding to the metal. Were we report a complexation process which enables the two faces of a prochiral diene to be differentiated for the first time, resulting in the production of optically active tricarbonyliron complexes. Various a,B-unsaturated ketones, which form moderately stable tricarbonyliron complexes, are known to act as a convenient source of an iron carbonyl moiety for transfer to 1,3-dienes.l Analogous transfer reagents prepared simply from two readily available chiral enones, (+)-pulegone (I) and (-)-3B-acetyloxypregna-5,16-diene-lo-one (II), (16-DHA) were used without isolation to provide a direct synthesis of optically active complexes of 1-methoxycyclohexa-1,3-diene (III), 1-methoxy-4-methylcyclohexa-1,3-diene (IV) and methyl sorbate (V), as shown in the Table. Complexes of pulegone3 were prepared thermally from Fe2(CO)S (light petroleum, b.p. 40-60°, 5 hrs). After filtration through celite , evaporation of solvent and Fe(C0)5, addition of the 1,3-diene in degassed benzene, toluene or light petroleum (b.p. 40-60') and heating at reflux for the appropriate time, the crude product was distilled and chromatographed on silica gel. The compounds were distilled a second time and optical rotations measured on analytically pure samples. A similar method was used for 3@acetyloxypregna-5,16-diene-ZO-one, except that crystallisation of the crude product from hexane resulted in

Chemischer Informationsdienst, Apr 15, 1980

Chemischer Informationsdienst, Nov 16, 1982

Die Estergruppe in den Cyclohexadienen (Ia) und (Ib) begünstigt die stereoselektive Komplexbildun... more Die Estergruppe in den Cyclohexadienen (Ia) und (Ib) begünstigt die stereoselektive Komplexbildung der β‐Isomeren (IIa) (dominierende Komponente im trennbaren Gemisch mit (IIIa) und (IVa); Gesamtausb.

Polymer-plastics Technology and Engineering, Jul 10, 2007

... Alireza Ashori a * & Warwick D. Raverty b pages 683-687. ... [Web of Science ®] View all ... more ... Alireza Ashori a * & Warwick D. Raverty b pages 683-687. ... [Web of Science ®] View all references 4 4. Ashori , A. ; Jalaluddin , H. ; Wan , Md. ; Zin , WY ; Mohd Nor , MY 2006 . Polymer-Plastics Technology and Engineering Journal 2006 , 45 ( 1 ), 125 – 129 . ...

Frontiers research topics, 2020

Lignocellulose is the only renewable carbon source that can help replace oil-based chemicals and ... more Lignocellulose is the only renewable carbon source that can help replace oil-based chemicals and materials, in the process fighting global warming. However, because of its chemical and structural complexity, lignocellulose transformation into advanced products requires a better understanding of its composition and of its architecture at different scales, as well as a combination of physical, biological, and chemical processes, in order to render this transformation efficient and economically competitive. Tremendous efforts continue to be made toward the production of ethanol as a biofuel from various lignocellulosic feedstocks. Furthermore, recent successes have been achieved in extracting fibers to prepare composite materials that can compete with plastic fabrics. Importantly, lignocellulose chemistry can bring to the market original and complex chemicals that can lead to new applications, in particular when exploiting aromatic molecules or oligosaccharides from lignocellulose to produce solvents, surfactants, plasticizers, functional additives for food/feed/cosmetics, drugs, monomers, and polymers. In addition to this broad range of molecular products, fibers and particles fractionated from the lignocellulosic biomass are increasingly used to elaborate bio-based composite materials

Australian Journal of Chemistry, 1978

Pigments of the Australian lacciferid, Austrotachardia acaciae Maskell, differ from those of Indi... more Pigments of the Australian lacciferid, Austrotachardia acaciae Maskell, differ from those of Indian lac insects in that the major constituent is xantholaccaic acid B (9) rather than a mixture of laccaic acids. Its structure has been determined by single-crystal X-ray diffraction of a new hexamethyl derivative. Xantholaccaic acids have not previously been found in nature. Earlier parts of this series have examined species from within the coccoid families Asterolecaniidae, Coccidae, Eriococcidae and ~seudococcidae.' All contained polyketide anthraquinones or related systems. This paper is concerned with a further family, Lacciferidae, exemplified by the species Austrotachardia acaciae aske ell.^'^ This ranges over the dry inland areas of Australia, parasitizing mulga and allied species of Acacia. It is related to the Indian lac insect Laccifer lacca Kerr, the source of lac dyestuffs and of shellac? The lac pigments have been studied by Sch~field,~ V e n k a t a r a m a~~~'~ and their coworkers. They include deoxyerythrolaccin (l), erythrolaccin (2), isoerythrolaccin (3) and laccaic acid D (4), and a complex series of polar laccaic acids A, B, C and E, formulated as (5), (6), (7) and (8) respectively. Because of their complexity structures (5)-(8) have not been confirmed by synthesis or degradation to known products. Samples of A. acaciae were taken from several different hosts at widely separated localities in Western Australia. Both living and degenerate specimens were examined. A11 afforded qualitatively similar mixtures of pigments but the best yields were obtained from living insects. Intractable, presumably polymeric, materials appeared to develop with aging. As in the case of L. lacca the mature insects were embedded in very large quantities of their own exuded resin. The components of this resin ranged widely in polarity,

Chemischer Informationsdienst, Jun 1, 1982

Reaktionen an zahlreichen Tricarbonyl‐n‐cyclohexadien‐eisen(0)‐Komplexen werden unter Berücksicht... more Reaktionen an zahlreichen Tricarbonyl‐n‐cyclohexadien‐eisen(0)‐Komplexen werden unter Berücksichtigung sterischer Gegebenheiten untersucht.

Chemischer Informationsdienst, Nov 16, 1982

Chemischer Informationsdienst, Mar 27, 1979