A study of the synthesis of triazoles using microwave irradiation

Molecular Diversity

Volumn 7, Issue 2-4, 2003, Pages 171-174

  Savin, Kenneth A ^a   Robertson, Michael ^a   Gernert, Doug ^a   Green, Steven ^a   Hembre, Erik J ^a   Bishop, Jessie ^a  

^a ELI LILLY AND COMPANY   (United States)

Author keywords

3+2 cycloaddition; Flow through reaction; Microwave irradiation; Montmorillonite (K 10) clay; Triazole

Indexed keywords

ACETYLENE; AZIDE; SOLVENT; TRIAZOLE DERIVATIVE;

ARTICLE; CHEMICAL MODIFICATION; CHEMICAL REACTION; CYCLOADDITION; HIGH TEMPERATURE; METHODOLOGY; MICROWAVE IRRADIATION; PRIORITY JOURNAL; REACTION ANALYSIS; REACTION TIME; SYNTHESIS; TEMPERATURE DEPENDENCE;

ACETYLENE; CHEMISTRY, ORGANIC; MICROWAVES; MODELS, CHEMICAL; SOLVENTS; TEMPERATURE; TRIAZOLES;

EID: 0347717653     PISSN: 13811991     EISSN: None     Source Type: Journal    
DOI: 10.1023/B:MODI.0000006801.27748.3b     Document Type: Article

References (30)

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3. The material described in this paper was previously disclosed at the 1st International Microwaves in Chemistry Conference, 7-9 March 2003, in Gainesville, Florida.
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17. a) All reactions were performed in a CEM Explorer microwave reactor with stirring and cooling on. All reactions were run in 'Power Flux' mode to maintain the temperature as specified. All reactions were run at 1 mmol scale with a slight (1.05-1.5 eq) excess of the azide. Ratios were determined using a HP 6890 plus GC system and values are corrected. Materials were purified using Radial Plate Chromatography and a gradient elution (100 mL Hexanes, 100 mL 10% EtOAc in Hexanes, 35% EtOAc in Hexanes, 50% EtOAc in Hexanes, 85% EtOAc in Hexanes) and the products MS, NMR and physical properties were compared to and matched the literature data (Ref. 7).
18. b) Flow-through reactions were run in a CEM Voyager model prototype. The tube used was a PTFE 1 mm tube sheathed in Kevlar® fiber and had a 10 mL total capacity within the reactor chamber. Residence time is defined here as the actual time the material in transit through the tube in the reactor is exposed to the microwave field. In the flow-through reacfion example, temperature was monitored using a feedback thermocouple probe that was provided with the microwave unit.
19. Although outside of the scope of this disclosure, we do intend to investigate the change in regioisomeric ratios that are the result of modifications to parameters such as temperature, concentration and power of the microwave field and will describe our results in the future. Also, as recommended by the reviewers, we will explore the effect from a computational angle to gain better insight into this process.
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