Halogen-zinc exchange reactions

The exchange reaction is catalyzed by various metal salts and complexes, such as Cul or CuCN [87], PdCl2(dppf) (dppf, l,l -bis(diphenylphosphino)ferrocene) [88], and Ni(acac)2 (acac, acetylacetonate) [89], allowing for shorter reaction times and the use of reduced amounts of diethylzinc. In the last two cases, the exchange reaction can also be conducted on alkyl bromides and even chlorides. Interestingly, 

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The cross-coupling of alkynylzinc halides or fluorinated alkenylzinc halides with fluori-nated alkenyl iodides allows the preparation of a range of fluorinated dienes or enynes - Functionalized allylic boronic esters can be prepared by the cross-coupling of (dialkylbo-ryl)methylzinc iodide 428 with functionalized alkenyl iodides. The intramolecular reaction provides cyclized products, such as 429 (Scheme 109) ° °. In some cases, reduction reactions or halogen-zinc exchange reactions are observed. 

C. Preparation of Mixed Zincates by Halogen-Zinc Exchange Reaction. . . 688... 

Table 5.10 Halogen-zinc exchange reaction in the presence of P4...

Ueno, M., Wheatley, A.E.H. and Kondo, Y. (2006) Phosphazene base-promoted halogen-zinc exchange reaction of aryl iodides using diethylzinc. Chemical Communications, 3549-3550. 

Kondo Y, Takazawa N, Yamazaki C, Sakamoto T (1994) Halogen-zinc exchange reaction of haloaromatics with lithium trimethylzincate. J Org Chem 59 4717-4718. doi 10.1021/ Jo00096a005... 

Nakamura 8, Liu C-Y, Muranaka A, Uchiyama M (2009) Theoretical study on the halogen-zinc exchange reaction by using organozincate compounds. Chem Eur J 15 5686-5694. doi 10.1002/chem.200802393... 

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