Noncryogenic I/Br-Mg Exchange of Aromatic Halides Bearing Sensitive Functional Groups Using i-PrMgCl-Bis[2-(N,N-dimethylamino)ethyl] Ether Complexes
Xiao-jun Wang,* Xiufeng Sun, Li Zhang, Yibo Xu, Dhileepkumar Krishnamurthy and Chris H. Senanayake
*Department of Chemical Development, Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, Connecticut 06877, Email: xwangrdg.boehringer-ingelheim.com
X.-J. Wang, X. Sun, L. Zhang, Y. Xu, D. Krishnamurthy, C. H. Senanayake, Org. Lett., 2006, 8, 305-307.
DOI: 10.1021/ol052704p (free Supporting Information)
The presence of bis[2-(N,N-dimethylamino)ethyl] ether allows a selective halide-magnesium exchange of iodo- and bromoaromatics bearing sensitive carboxylic ester and cyano groups with isopropylmagnesium chloride. A subsequent reaction with trimethylborate as electrophile afforded arylboronic acids in good to excellent yields.
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