Zobrazeno 1 - 10
of 66
pro vyhledávání: '"Ian C. Lennon"'
Autor:
Shaun Jones, Ian C. Lennon, Paul Harrison, Raymond E. Conrow, Christel Kronig, Shaun Simmonds, Mark Jackson
Publikováno v:
Organic Process Research & Development. 15:301-304
A robust synthesis of (5Z,8Z,11Z,13E)(15S)-15-hydroxyeicosa-5,8,11,13-tetraenoic acid (15(S)-HETE) sodium salt was established, utilising a biooxidation process. Treatment of arachidonic acid with soybean lipoxidase in 0.1 M sodium tetraborate buffer
Publikováno v:
Accounts of Chemical Research. 40:1291-1299
This Account provides an overview of our activities in the area of asymmetric hydrogenation over the last 12 years. We discuss the manufacture of metal-containing precatalysts and their use in asymmetric hydrogenation processes. Many of the metal com
Publikováno v:
Tetrahedron Letters. 48:4623-4626
A synthesis of N-acetylcolchinol, a key intermediate in the synthesis of ZD6126, was developed. The enantiodifferentiating step required the catalytic asymmetric hydrogenation of an enamide. After screening a range of metal and ligand combinations it
Publikováno v:
Tetrahedron Letters. 48:945-948
A synthesis of (1R,2S)-dehydrocoronamic acid ethyl ester was developed employing a regio- and enantioselective palladium-catalysed nucleophilic ring-opening of 3,4-epoxy-1-butene with a glycine anion equivalent as the key enantiodifferentiating step.
Publikováno v:
Organic Process Research & Development. 10:1054-1058
Stoichiometric sodium borohydride is frequently used in the chemoselective reduction of ketones to racemic secondary alcohols. Catalytic homogeneous hydrogenation using (diphosphine)RuCl2(diamine) complexes provides a practical and economic alternati
Autor:
Céline Praquin, Helen J. Samuel, Ian Appleby, Niamh Willis, James A. Ramsden, Christopher J. Cobley, Pieter D. de Koning, Catherine Hill, Lee T. Boulton, Mike L. Hughes, Ian C. Lennon
Publikováno v:
Organic Letters. 7:1931-1934
Two methods to produce (2S)-5-amino-2-(1-n-propyl-1H-imidazol-4-ylmethyl)-pentanoic acid were investigated. Diastereoisomeric salt resolution, using the quinidine salt, gave the desired intermediate in 98% ee and 33% yield. Asymmetric hydrogenation o
Publikováno v:
Tetrahedron Letters. 46:983-986
A method for the coupling of acyl and imino substituents to the sterically encumbered 5-position of a 4-aminoquinazoline was developed. Starting with a 4-amino-5-iodoquinazoline, the method employs a facile intramolecular zinc-mediated transfer from
Publikováno v:
Synthesis. 2003:1639-1642
Asymmetric hydrogenation is becoming an increasingly prevalent technology for the manufacture of complex pharmaceutical intermediates. Drawing from Chirotech's experience over the past eight years, this article emphasisesthe need for a diverse cataly
Autor:
Christopher J. Cobley, and Céline Praquin, Antonio Zanotti-Gerosa, Ian C. Lennon, Angela C. Sutterer, and Christian T. Goralski, Robert B. Appell
Publikováno v:
Organic Process Research & Development. 7:407-411
An extremely efficient route to highly enantiomerically enriched 2-methylsuccinamic acid via asymmetric hydrogenation has been developed. By using [(S,S)-Et-DuPHOS Rh COD]BF4 as the precatalyst und...
Autor:
David A. Chaplin, Graham Meek, Julian P. Henschke, Antonio Zanotti-Gerosa, Paul H. Moran, James A. Ramsden, Paul H. M. Harrison, Christopher J. Pilkington, Ian C. Lennon, Simon Watkins
Publikováno v:
Organic Process Research & Development. 7:89-94
The practicalities of the asymmetric hydrogenation of acetophenone derivatives are addressed. The catalysts used, derived from the precatalysts [(xylylPhanePhos)RuCl2(DPEN)] (S)-(R,R)-1 and (R)-(S,S)-1, were shown to possess very high reactivity. 4