Carbon-halogen bond-formation

This regioselectivity results from the capto dative effect of intermediate radicals which are stabilized by the presence of one electron-donor and one electron-acceptor substituents [2]. The stereoselectivity of a-bromosubstitution is in agreement with the 

In the case of 1-halogeno 1-deoxy sugars, the competition of photobromination at C-5 or C-l depends on the halogen and its configuration. The regioselectivity of the reaction at C-l decreases from anomeric chlorides to fluorides, and the a-deri-vatives are less reactive or inert for the anomeric substitution. 

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Significantly, the pre-exponential factors decrease with increasing reactivity, and this suggests that the Wheland intermediate is more nearly formed in the transition state, the more reactive the compound. Or, considered another way, the position along the reaction co-ordinate at which a given amount of carbon-halogen bond formation occurs is nearer to the ground state the more reactive the compound. 

Polymerization with Carbon-Halogen Bond Formation.125... 

CARBON-NITROGEN, CARBON-OXYGEN, CARBON-SULPHUR AND CARBON-HALOGEN BOND FORMATION... 

This reactive group of reagents has lost some of its previous universal synthetic utility due to obnoxious and poisonous characteristics. Only minor developments have taken place during the last decade in its application to carbon-halogen bond formation. 

Formation of the C— F bond mostly requires conditions different from all other carbon-halogen bond formations. 

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