A safe and efficient synthetic route to a 2,5-dimethyl-1-aryl-1H-imidazole intermediate

Organic Process Research and Development

Volumn 15, Issue 2, 2011, Pages 449-454

  Barrios Sosa, Ana C ^a   Williamson, R Thomas ^a   Conway, Ryan ^a   Shankar, Ashish ^a   Sumpter, Rosline ^a   Cleary, Thomas ^a  

^a Roche Carolina   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

1H-IMIDAZOLE; CATALYZED REACTIONS; ETHYNYL; INTRAMOLECULAR CYCLIZATIONS; PROOF OF CONCEPT; REACTION MECHANISM; SYNTHETIC ROUTES;

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; OPTIMIZATION; REACTION INTERMEDIATES; SYNTHESIS (CHEMICAL);

PLANTS (BOTANY);

EID: 79952841678     PISSN: 10836160     EISSN: 1520586X     Source Type: Journal    
DOI: 10.1021/op100335q     Document Type: Article

References (20)

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20. Thermal stability of the reaction mixture was assessed with accelerating rate calorimetry (ARC, Thermal Hazard Technology: EuroARC) using a standard heat-wait-search (HWS) approach. A sample of the reaction mixture after completion of the reaction was tested in an ARC-the sample showed a minor self-heating exotherm with an onset at 82 °C. The exotherm did not show acceleration of self-heat rates or generation of pressure with the system falling back into HWS mode at 125 °C. A second decomposition exotherm is seen with an onset at 218 °C, accelerating self-heat-rates and gas generation and a maximum calculated final adiabatic temperature of 406.8 °C. A standard safety margin of 50 °C from the exothermic onset at 218 °C gives a maximum safe temperature of 168 °C.