Rapid palladium-catalyzed C3-arylation of 2(1H)-pyrazinones: Effect of simultaneous cooling on microwave-assisted reactions on solid support

Synlett

Volumn , Issue 19, 2008, Pages 3021-3025

  Singh, Brajendra K ^a,b   Parmar, Virinder S ^b   Van Der Eycken, Erik ^a  

^a UNIVERSITY OF LEUVEN   (Belgium)

^b UNIVERSITY OF DELHI   (India)

Author keywords

2(1H) pyrazinones; Microwave; Palladium catalysis; Simultaneous cooling; Solid support

Indexed keywords

BORONIC ACID DERIVATIVE; PALLADIUM; POLYMER; PYRAZINE DERIVATIVE;

ARTICLE; ARYLATION; CATALYSIS; CATALYST; COOLING; DECOMPOSITION; HEATING; MICROWAVE IRRADIATION; REACTION OPTIMIZATION;

EID: 57649136401     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-0028-1083631     Document Type: Article

References (16)

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14. See power profile in Supporting Information.
15. All microwave-irradiation experiments were carried out in a dedicated CEM-Discover-Coolmate monomode microwave apparatus (CEM Corporation P.O. Box 200 Matthews, NC 28106), operating at a frequency of 2.45 GHz with continuous irradiation power from 0-300 W. Reaction mixtures were efficiently stirred with a magnetic stirrer. The reactions were carried out in an open 10 mL double-walled glass vial which was cooled to 0-35°C using a microwave transparent cooling liquid. The temperature of the cooling liquid was between 15°C and 18°C Irradiation and cooling were started simultaneously, starting with the reaction mixture at r.t. The temperature was measured with a fiberoptic probe device inserted into the reaction vessel; a schematic representation of the setup can be found at http://cemsynthesis.com
16. 13C NMR, and HRMS) of all new compounds are available in the Supporting Information.