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Synlett 2005(11): 1783-1786  
DOI: 10.1055/s-2005-871572
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© Georg Thieme Verlag Stuttgart · New York

Zr-Catalyzed Coupling Reaction of Alkyl Halides, Tosylates, and Sulfates with β-Phenethyl Grignard Reagents via Styrene-Zirconate Intermediates

Jun Terao, Shameem Ara Begum, Akihiro Oda, Nobuaki Kambe*
Department of Applied Chemistry & Science and Technology Center for Atoms, Molecules and Ions Control, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 565-0871, Japan
Fax: +81(6)68797390; e-Mail: kambe@chem.eng.osaka-u.ac.jp;
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Publication History

Received 2 May 2005
Publication Date:
28 June 2005 (online)

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Abstract

β-Phenethylmagnesium chlorides react with alkyl halides, tosylates, and sulfates in the presence of a catalytic amount of Cp2ZrCl2 to afford 2-arylalkanes via alkylation of styrene-zirconate intermediates at the benzylic position. Competitive reaction using mixtures of alkyl halides (alkyl-X; X = F, Cl, Br) showed that the reactivities of the halides increase in the order of alkyl-Cl < alkyl-F < alkyl-Br with the relative rates of 1:19:428.

Key words

zirconocene - β-phenethyl Grignard reagent - coupling reaction - alkyl halide - alkyl tosylate

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