Document Detail

Continuous flow reaction monitoring using an on-line miniature mass spectrometer.
MedLine Citation:
PMID:  22847699     Owner:  NLM     Status:  In-Data-Review    
RATIONALE: A recently developed miniature electrospray ionisation mass spectrometer has been coupled to a preparative flow chemistry system in order to monitor reactive intermediates and competing reaction paths, screen starting materials, and optimise reaction conditions. Although ideally suited to the application, mass spectrometers have rarely been used in this way, as traditional instruments are too bulky to be conveniently coupled to flow chemistry platforms.
METHODS: A six-port switching valve fitted with a 5 μL loop was used to periodically sample the flow stream leaving the reactor coil. Mass spectra corresponding to the sample loop contents were observed approximately 10 s after activating the valve. High fluidic pressure was maintained throughout to ensure that gaseous products remained in solution. As an illustrative example of how this apparatus can be employed, the generation of benzyne and its subsequent reaction with furan were investigated. Benzyne was prepared via diazotisation of anthranilic acid using tert-butyl nitrite.
RESULTS: Unexpectedly, the explosive diazotised intermediate was detected by the mass spectrometer at low coil temperatures or short residence times. The optimum reactor temperature and residence time for production of the desired Diels-Alder product are 50 °C and 3-5 min, respectively. There are competing reaction pathways leading to the formation of acridone and several other by-products.
CONCLUSIONS: On-line mass spectrometry allowed the flow conditions to be quickly tuned for safe operation and optimal generation of the desired product. The validity of this approach was corroborated by off-line liquid chromatography/mass spectrometry (LC/MS) analysis of flow samples. Copyright © 2012 John Wiley & Sons, Ltd.
Duncan L Browne; Steven Wright; Benjamin J Deadman; Samantha Dunnage; Ian R Baxendale; Richard M Turner; Steven V Ley
Related Documents :
22740259 - Accurate analysis of trace earthy-musty odorants in water by headspace solid phase micr...
24469599 - Thermal degradation kinetics and decomposition mechanism of pbsu nanocomposites with si...
24552299 - Four assay designs and on-chip calibration: gadgets for a sepsis protein array.
22606839 - Temporal analysis of sesquiterpene emissions from manuka and phoebe oil lures and effic...
22887709 - Surfactant roles in modern sample preparation techniques: a review.
23902019 - Alteration of gas phase ion polarizabilities upon hydration in high dielectric liquids.
15206839 - Identification and semi-quantitative determination of gum arabic in wines by gc-ms and ...
16405979 - Quantification of chloroanisoles in cork using headspace solid-phase microextraction an...
2674179 - Determination of unlabeled and 13c6-labeled moricizine in human plasma using thermospra...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Rapid communications in mass spectrometry : RCM     Volume:  26     ISSN:  1097-0231     ISO Abbreviation:  Rapid Commun. Mass Spectrom.     Publication Date:  2012 Sep 
Date Detail:
Created Date:  2012-07-31     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8802365     Medline TA:  Rapid Commun Mass Spectrom     Country:  England    
Other Details:
Languages:  eng     Pagination:  1999-2010     Citation Subset:  IM    
Copyright Information:
Copyright © 2012 John Wiley & Sons, Ltd.
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Identification, quantification and carbon stable isotopes determinations of organic acids in monoflo...
Next Document:  Characterization of lipid A profiles from Shigella flexneri variant X lipopolysaccharide.