Search results
Results from the WOW.Com Content Network
In chemistry, an electrophile is a chemical species that forms bonds with nucleophiles by accepting an electron pair. [1] Because electrophiles accept electrons, they are Lewis acids . [ 2 ] Most electrophiles are positively charged , have an atom that carries a partial positive charge, or have an atom that does not have an octet of electrons.
Alkyl Grignard reagents, [16] alkylithium compounds, [17] alkylzinc compounds, [18] and alkylcuprates [19] have been aminated with electrophilic reagents successfully. Among sp 2 -centered carbanions, vinyllithium compounds, [ 8 ] vinylcuprates, [ 20 ] and vinyl Grignard reagents [ 21 ] react with electrophilic aminating reagents to afford ...
Cross electrophile coupling is a type of cross-coupling reaction that occurs between two electrophiles. It is often catalyzed by transition metal catalyst(s). Unlike conventional cross-coupling reactions of an electrophile with an organometallic reagent, [1] the coupling partners in cross electrophile coupling reactions are both electrophiles. [2]
Electrophilic fluorination is the combination of a carbon-centered nucleophile with an electrophilic source of fluorine to afford organofluorine compounds.Although elemental fluorine and reagents incorporating an oxygen-fluorine bond can be used for this purpose, they have largely been replaced by reagents containing a nitrogen-fluorine bond.
The steric interaction between the pyrrolidine ring and the electrophilic reagent hinders the attack of the electrophile from the top face. On the contrary, when the electrophile attacks from the bottom face, such unfavorable interaction does not exist. Therefore, the electrophilic attack proceeds from the sterically more accessible face. [18]
In this electrophilic aromatic substitution reaction, the aryldiazonium cation is the electrophile, and the activated carbon (usually from an arene, which is called coupling agent), serves as a nucleophile. Classical coupling agents are phenols and naphthols. [1] Usually the diazonium reagent attacks at the para position of the coupling agent.
Only the exotic dimethylhalonium reagents ([Me 2 X] + [SbF 6] −, X = Cl, Br, I), methyl carboranate reagents, and the transiently-generated methyldiazonium cation (MeN + 2) are stronger sources of electrophilic methyl. Due to its high reactivity, it is rapidly destroyed by atmospheric moisture and best stored in an inert atmosphere glovebox ...
While electrophilic fluorination is possible with F 2 /N 2 (10%), XeF 2, or N-F reagents like Selectfluor, these methods are seldom used, due to the formation of isomeric mixtures and polyfluorination products. [5]