Practical access to metallo thiophenes: Regioselective synthesis of 2,4-disubstituted thiophenes

Organic Process Research and Development

Volumn 14, Issue 6, 2010, Pages 1427-1431

  Asselin, Sylvie M ^a   Bio, Matthew M ^a   Langille, Neil F ^a   Ngai, Ka Yi ^a  

^a AMGEN INC   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AGE EFFECTS; CHEMO-SELECTIVITY; CRYOGENIC CONDITIONS; FUNCTIONALIZATIONS; GRIGNARD REAGENT; IN-SITU; METALATIONS; METHYLTHIOPHENE; PHTHALAZINONE; PHTHALIC ANHYDRIDES; PROLONGED REACTION; REGIOSELECTIVE MAGNESIATION; REGIOSELECTIVE SYNTHESIS; TRANSMETALATION;

ECONOMIC ANALYSIS; LITHIUM; MAGNESIUM; REGIOSELECTIVITY; SYNTHESIS (CHEMICAL); THIOPHENE;

ORGANIC POLYMERS;

EID: 78649651002     PISSN: 10836160     EISSN: 1520586X     Source Type: Journal    
DOI: 10.1021/op100226k     Document Type: Article

References (37)

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36. In a power compensation calorimetry experiment conducted at 10°C isothermal, quenching the reaction with water (4 volumes over 1 h, 60.6 mmol scale) resulted in a 74 kJ/mol exotherm, uncorrected for heat of mixing.
37. This reaction proceeds below the flash point of 35% hydrazine/water (112.7°C) and below the boiling point of a hydrazine/water azeotrope (120.3°C). DSC and ARC scanning of the reaction components at 300 and 250°C, respectively, showed no unsafe thermodynamic events.