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Lewis Acid Directed Regioselective Metalations of Pyridazine
Moritz Balkenhohl1, Harish Jangra1, Tobias Lenz1
1Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
Abstract:
Mono- or bidentate boron Lewis acids trigger a regioselective magnesiation or zincation of pyridazine in position C3 (ortho product) or C4 (meta product). The regioselectivity of the metalation was rationalized with the help of calculated pKa values of both pyridazine and pyridazine/Lewis acid complexes.
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