2006

Halogen compoundsQ 0090 Synthesis of the Multisubstituted Halogenated Olefins via Cross-Coupling of

Dihaloalkenes with Alkylzinc Bromides. — In the presence of Pd(PPh3)4, 1-fluo-ro-1-iodoalkenes as well as 1-fluoro-1-bromo- and 1-fluoro-1-chloroalkenes undergo stereoselective reaction with alkylzinc bromides to afford (Z)-fluoroalkenes. With PdCl2(dppb) higher yields are obtained, but sometimes small amounts of (E)-isomers are also formed. (Z)-Chloroalkenes are available from 1,1-dichloroalkenes. In contrast, 1,1-dibromoalkenes yield dialkylated products instead of bromoalkenes. — (ANDREI, D.; WNUK*, S. F.; J. Org. Chem. 71 (2006) 1, 405-408; Dep. Chem. Biochem., Fla. Int. Univ., Miami, FL 33199, USA; Eng.) — Jannicke

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