John Leonard - Profile on Academia.edu (original) (raw)
Papers by John Leonard
Chapter 6 Preparation of substituted 3-sulfolenes and their use as precursors for diels-alder dienes
Organosulfur Chemistry, 1998
Stereoconservative synthesis of dihydromeroquinene (cincholoipon) from secologanin
Tetrahedron Letters, 1978
Short enantioselective approach to heteroyohimbine alkaloids from meso-bicyclo[3.3.0]octane-3,7-dione: synthesis of methyl 2-epielenolate
Journal of the Chemical Society, Perkin Transactions 1, 1992
Highly selective stereochemically controlled five-versus six-membered acetal ring cyclisation
Journal of the Chemical Society, Chemical Communications, 1993
Asymmetric alkylation of N-pivaloyl-o-benzylaniline
Tetrahedron: Asymmetry, 2004
... We also repeated the reaction with 2-furaldehyde carried out by Schwartz and Yates using sec-... more ... We also repeated the reaction with 2-furaldehyde carried out by Schwartz and Yates using sec-BuLi/(−)-sparteine instead of n-BuLi/TMEDA (Scheme 4). We obtained adduct 14 in a 90% overall yield as an approximately 1:1 mixture of diastereomers. ...
Total synthesis of specionin - natural product or artifact ?
Tetrahedron Letters, 1987
The iridoid insect antifeedant specionin has been synthesised from endo-cis-bicyclo[3.3.0]oct -7-... more The iridoid insect antifeedant specionin has been synthesised from endo-cis-bicyclo[3.3.0]oct -7-en-2-ol. When the bis acetal ring is cyclised at a late stage the correct stereochemistry is generated selectively. ... Specionin 2 has been synthesised from 4. Acid catalysed cyclisation of the ...
Tetrahedron Letters, 1977
A short enantioselective route to corynanthe alkaloid precursors
Tetrahedron Letters, 1990
... Chem. Soc., (1984) 106, 5754 7. We thank Dr. RT Brown for a comparison sample and spectra of ... more ... Chem. Soc., (1984) 106, 5754 7. We thank Dr. RT Brown for a comparison sample and spectra of methyl elenolate. 8. a)RTBrown, CL Chapple, DM Duckworlh and R. Plait, J. Chem. Soc. ... We thank Dr. RT Brown for a comparison sample and spectra of methyl elenolate. ...
A short synthesis of apoyohimbines via a sulfolene based intramolecular Diels-Alder reaction
Tetrahedron Letters, 1994
... 94 6.00+0.00 A Short Synthesis of Apoyohimbines via a Sulfolene Based Intramolecular DielsAld... more ... 94 6.00+0.00 A Short Synthesis of Apoyohimbines via a Sulfolene Based Intramolecular DielsAlder Reaction John Leonard,* Diana Appleton and ... 3303; e) SF Martin, T. Rein, Y. Liao, Tetrahedron Lelt.. ... 6. J. Leonard, SP Peamley and DMB Hickey, Synletf, 1992, 272 7. TS Chou. ...
![Research paper thumbnail of Enantioselective opening of spiro epoxides derived from cis bicyclo[3.3.0]octan-3,7-dione using chiral lithium amide bases](https://attachments.academia-assets.com/66770774/thumbnails/1.jpg)
](Tetrahedron Letters, 1990
Preparation of proline derived lithium amide bases and their use in enantioselective deprotonation of meso epoxides
Tetrahedron, 1987
... Shirley K. Hendrie and John Leonard ... Infra red spectra were recorded on a Peiktn Elmer 397... more ... Shirley K. Hendrie and John Leonard ... Infra red spectra were recorded on a Peiktn Elmer 397 spectrometer and NMR spectra were measured at 60 MHz on a Varian EM 360 Instrument, at 90 MHz on a Peikki Elmer R32 instrument, at 300 MHz on a Broker AC 300 Instalment or at ...
Efficient Procedures for in situ Trapping of (R)- and (S)-Glyceraldehyde acetonides by Stabilized Wittig Reagents
Synthetic Communications, 1989
Practical, high yielding procedures are described whereby useful chiral enones and enoates can be... more Practical, high yielding procedures are described whereby useful chiral enones and enoates can be prepared from either (R)- or (S)-glyceraldekyde acetonide. The labile aldehydes, formed from their precursors by lead tetraacetate cleavage, we reacted with stabilized Wittig reagents in situ.
Synlett, 2010
A Morita-Baylis-Hillman-type reaction has been applied to the asymmetric preparation of azaspiroc... more A Morita-Baylis-Hillman-type reaction has been applied to the asymmetric preparation of azaspirocycles in high yield and diastereoselectivity. The optimisation of the reaction is discussed and a model for the origin of diastereoselectivity is proposed.
Selective Conjugate Addition of Organolithium Reagents to γ,δ-Unsaturated β-Oxo Esters Derived from Glyceraldehyde Acetonide
Synlett, 1992
Stereoselective Conjugate Addition of Organolithium Reagents to Enoates Derived from Glyceraldehyde Acetonide
Synlett, 1990
Recent progress in the chemistry of monoterpenoid indole alkaloids derived from secologanin
Natural Product Reports, 1999
Synthetic, structural, and mechanistic studies of the carbon-hydrogen bond activation of phenols by tungsten complexes W(PMe3)6 and W(PMe3)4(.eta.2-CH2PMe2)H
Journal of the American Chemical Society, 1992
RefDoc Bienvenue - Welcome. Refdoc est un service / is powered by. ...
European Journal of Pharmacology, 2007
Novel, 2′-hydroxy derivatives of fendiline have been synthesised and their ability to induce rela... more Novel, 2′-hydroxy derivatives of fendiline have been synthesised and their ability to induce relaxation of isolated rat small mesenteric and coronary arteries were determined. Both derivatives examined were significantly more potent as vasodilators than fendiline itself. Similar effects were observed on both mesenteric and coronary arteries.
Control of Asymmetry Through Conjugate Addition Reactions
European Journal of Organic Chemistry, 1998
ABSTRACT
Chapter 6 Preparation of substituted 3-sulfolenes and their use as precursors for diels-alder dienes
Organosulfur Chemistry, 1998
Stereoconservative synthesis of dihydromeroquinene (cincholoipon) from secologanin
Tetrahedron Letters, 1978
Short enantioselective approach to heteroyohimbine alkaloids from meso-bicyclo[3.3.0]octane-3,7-dione: synthesis of methyl 2-epielenolate
Journal of the Chemical Society, Perkin Transactions 1, 1992
Highly selective stereochemically controlled five-versus six-membered acetal ring cyclisation
Journal of the Chemical Society, Chemical Communications, 1993
Asymmetric alkylation of N-pivaloyl-o-benzylaniline
Tetrahedron: Asymmetry, 2004
... We also repeated the reaction with 2-furaldehyde carried out by Schwartz and Yates using sec-... more ... We also repeated the reaction with 2-furaldehyde carried out by Schwartz and Yates using sec-BuLi/(−)-sparteine instead of n-BuLi/TMEDA (Scheme 4). We obtained adduct 14 in a 90% overall yield as an approximately 1:1 mixture of diastereomers. ...
Total synthesis of specionin - natural product or artifact ?
Tetrahedron Letters, 1987
The iridoid insect antifeedant specionin has been synthesised from endo-cis-bicyclo[3.3.0]oct -7-... more The iridoid insect antifeedant specionin has been synthesised from endo-cis-bicyclo[3.3.0]oct -7-en-2-ol. When the bis acetal ring is cyclised at a late stage the correct stereochemistry is generated selectively. ... Specionin 2 has been synthesised from 4. Acid catalysed cyclisation of the ...
Tetrahedron Letters, 1977
A short enantioselective route to corynanthe alkaloid precursors
Tetrahedron Letters, 1990
... Chem. Soc., (1984) 106, 5754 7. We thank Dr. RT Brown for a comparison sample and spectra of ... more ... Chem. Soc., (1984) 106, 5754 7. We thank Dr. RT Brown for a comparison sample and spectra of methyl elenolate. 8. a)RTBrown, CL Chapple, DM Duckworlh and R. Plait, J. Chem. Soc. ... We thank Dr. RT Brown for a comparison sample and spectra of methyl elenolate. ...
A short synthesis of apoyohimbines via a sulfolene based intramolecular Diels-Alder reaction
Tetrahedron Letters, 1994
... 94 6.00+0.00 A Short Synthesis of Apoyohimbines via a Sulfolene Based Intramolecular DielsAld... more ... 94 6.00+0.00 A Short Synthesis of Apoyohimbines via a Sulfolene Based Intramolecular DielsAlder Reaction John Leonard,* Diana Appleton and ... 3303; e) SF Martin, T. Rein, Y. Liao, Tetrahedron Lelt.. ... 6. J. Leonard, SP Peamley and DMB Hickey, Synletf, 1992, 272 7. TS Chou. ...
Tetrahedron Letters, 1990
Preparation of proline derived lithium amide bases and their use in enantioselective deprotonation of meso epoxides
Tetrahedron, 1987
... Shirley K. Hendrie and John Leonard ... Infra red spectra were recorded on a Peiktn Elmer 397... more ... Shirley K. Hendrie and John Leonard ... Infra red spectra were recorded on a Peiktn Elmer 397 spectrometer and NMR spectra were measured at 60 MHz on a Varian EM 360 Instrument, at 90 MHz on a Peikki Elmer R32 instrument, at 300 MHz on a Broker AC 300 Instalment or at ...
Efficient Procedures for in situ Trapping of (R)- and (S)-Glyceraldehyde acetonides by Stabilized Wittig Reagents
Synthetic Communications, 1989
Practical, high yielding procedures are described whereby useful chiral enones and enoates can be... more Practical, high yielding procedures are described whereby useful chiral enones and enoates can be prepared from either (R)- or (S)-glyceraldekyde acetonide. The labile aldehydes, formed from their precursors by lead tetraacetate cleavage, we reacted with stabilized Wittig reagents in situ.
Synlett, 2010
A Morita-Baylis-Hillman-type reaction has been applied to the asymmetric preparation of azaspiroc... more A Morita-Baylis-Hillman-type reaction has been applied to the asymmetric preparation of azaspirocycles in high yield and diastereoselectivity. The optimisation of the reaction is discussed and a model for the origin of diastereoselectivity is proposed.
Selective Conjugate Addition of Organolithium Reagents to γ,δ-Unsaturated β-Oxo Esters Derived from Glyceraldehyde Acetonide
Synlett, 1992
Stereoselective Conjugate Addition of Organolithium Reagents to Enoates Derived from Glyceraldehyde Acetonide
Synlett, 1990
Recent progress in the chemistry of monoterpenoid indole alkaloids derived from secologanin
Natural Product Reports, 1999
Synthetic, structural, and mechanistic studies of the carbon-hydrogen bond activation of phenols by tungsten complexes W(PMe3)6 and W(PMe3)4(.eta.2-CH2PMe2)H
Journal of the American Chemical Society, 1992
RefDoc Bienvenue - Welcome. Refdoc est un service / is powered by. ...
European Journal of Pharmacology, 2007
Novel, 2′-hydroxy derivatives of fendiline have been synthesised and their ability to induce rela... more Novel, 2′-hydroxy derivatives of fendiline have been synthesised and their ability to induce relaxation of isolated rat small mesenteric and coronary arteries were determined. Both derivatives examined were significantly more potent as vasodilators than fendiline itself. Similar effects were observed on both mesenteric and coronary arteries.
Control of Asymmetry Through Conjugate Addition Reactions
European Journal of Organic Chemistry, 1998
ABSTRACT