Synthesis 2010(7): 1097-1106  
DOI: 10.1055/s-0029-1219231
© Georg Thieme Verlag Stuttgart ˙ New York

Regioselective Functionalization of Chlorophthalazine Derivatives

François Crestey, Paul Knochel*
Department Chemie und Biochemie, Ludwig-Maximilians-Universität, Butenandtstr. 5-13, 81377 München, Germany
Fax: +49(89)218077680; e-Mail:;
Further Information

Publication History

Received 18 November 2009
Publication Date:
20 January 2010 (eFirst)


Chlorophthalazines were efficiently metalated using tmpZnCl˙LiCl under microwave irradiation. This provided novel substituted phthalazine derivatives after subsequent trapping of the resulting organometallic reagents with various electrophiles. Moreover, Negishi cross-coupling reactions have been performed affording new polyfunctionalized phthalazine scaffolds in very good yields.


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Performing this reaction at lower temperatures did not avoid the ring opening of 1,6-dichlorophthalazine 1 giving the phthalonitrile 7 as the major product.


For the preparation of such benzylic and pyridinylzinc reagents, see ref. 14h.