Flow Synthesis Online - May 2010
Welcome to the Flow Synthesis Online newsletter.
This publication is released bi-monthly and will showcase new applications, events, and equipment in the Flow Synthesis world.
Applications |
| Flow Ozonolysis
|
| Free Laminated Vapour Pressure Chart
One of the key advantages of flow chemistry is the ability to run at elevated pressures, allowing volatile solvents to be heated way above their usual boiling points while remaining in the liquid state. But what pressure does a given solvent require to prevent it boiling ? Help is at hand - Vapourtec have a free laminated chart showing the correct values for all commonly used solvents. |
Product News |
| Pumping of BuLi now possible
But as a result of extensive development work and some new add on equipment, the Vapourtec R series can now be used for stable, reliable handling of these reagents. |
Events Attendees of the following events will be able to see the latest Vapourtec Flow Chemistry equipment in action, and no doubt talk to other users. |
| Eleventh Annual Symposium on Chemical Synthesis: Advances and Applications
25th June 2010, The CMLD at Boston University |
| American Chemical Society Fall 2010 National Meeting & Exposition
22-26 August, Boston USA |
| 1st RSC/SCI Symposium on Continuous Processing and Flow Chemistry
3-4 November, GlaxoSmithKline Stevenage, Herts, UK |
| UK Automated Synthesis Forum (UKASF)
16-17 November, MSD, Newhouse, UK |
Publications
|
| Flow Ozonolysis Using a Semipermeable Teflon AF-2400 Membrane To Effect Gas−Liquid Contact
Whiffen Laboratory, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, U.K. A flow-through chemistry apparatus has been developed which allows gases and liquids to contact via a semipermeable Teflon AF-2400 membrane. In this preliminary investigation, the concept was proven by application to the ozonolysis of a series of alkenes. |
| Continuous Flow Palladium(II)-Catalyzed Oxidative Heck Reactions with Arylboronic Acids
Luke R. Odell 1, Jonas Lindh 1, Tomas Gustafsson 2, Mats Larhed 1 * 1Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, Sweden Palladium(II)-catalyzed oxidative Heck reactions were investigated under continuous flow conditions. Selective, fast and convenient protocols for the coupling of arylboronic acids with electron-rich and electron-poor olefins were developed by using a commercially available flow reactor. |
| Reaction of Grignard reagents with carbonyl compounds under continuous flow conditions
a Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, Italy This contribution details how a continuous flow reactor was used to react carbonyl compounds with Grignard reagents at room temperature in an efficient and safe manner. Flow rate, residence time and temperature were optimized for the preparation of a small collection of secondary and tertiary alcohols. Excellent yields and general applicability were observed using the set-up protocol. The procedure was also applied for the preparation of Tramadol, an analgesic drug belonging to the opioid group. The developed conditions allowed the selective addition of Grignard reagents to aldehydes and ketones in the presence of a nitrile function. |
| A highly efficient flow reactor process for the synthesis of N-Boc-3,4-dehydro-l-proline methyl ester
Dipartimento di Scienze Farmaceutiche ‘Pietro Pratesi’, Università degli Studi di Milano, Italy The multi-step preparation of N-Boc-3,4-dehydro-l-proline methyl ester using a modular flow reactor is reported. The use of immobilised reagents and scavengers in pre-packed glass tubes allows us to obtain the pure product in 87% overall yield, 97% purity, and >98% enantiomeric excess without any additional purification step. Our flow-based protocol enables the rapid multi-gram synthesis (about 9 g/12 h) of the desired product. |
| Flow synthesis of tricyclic spiropiperidines as building blocks for the histrionicotoxin family of alkaloids
a CSIRO Molecular and Health Technologies, Australia A domino cyclization reaction of the bis-unsaturated ketone 3 with hydroxylamine proceeds with good yield and high stereoselectivity, in a flow reactor system. The tricyclic spiropiperidine products 5 and 2 obtained are valuable building blocks for the synthesis of analogues of the histrionicotoxin alkaloids. |
