Reactions nucleophilic/electrophilic

Nucleophilic Reagents. In contrast to electrophilic reactions, nucleophiles attack positively charged, even carbons ia the chain. The reactions lead to the exchanging of substituents or terminal residues. Thus, SR and OR groups, or halogen atoms can be exchanged by other suitable nucleophiles (4,69,70), for example, by aniline ... 

The reactions of NSF3 have been investigated in considerable detail. They can be classified under the following categories (a) reactions with electrophiles (b) addition to the SN triple bond and (c) reactions with nucleophiles. Some examples of these different types of behaviour are discussed below. 

Next, examine the highest-occupied and lowest-unoccupied molecular orbitals (HOMO and LUMO) of dichlorocarbene. Were the reaction a nucleophilic addition , how would you expect CCI2 to approach propene Were the reaction an electrophilic addition , how would you expect CCI2 to approach propene Which inteqDretation is more consistent with the geometry of the transition state ... 

Lone-pair electrons (Section 1.4) Nonbonding valence-shell electron pairs. Lone-pair electrons are used by nucleophiles in their reactions with electrophiles. 

Nucleophile (Section 5.4) A "nucleus-lover," or species that donates an electron pair to an electrophile in a polar bond-forming reaction. Nucleophiles are also Lewis bases. 

Not only because of their diminished electrophilic reactivity but also because of their propensity to undergo enolization and many other side reactions, nucleophilic alkylation of aliphatic aldehydes often suffers from low yields. Accordingly, the reaction that is successful for aromatic aldehydes is not necessarily successful for aliphatic aldehydes. 

A paper concerned with the synthesis of pyridazino[3,4-fe]indoles 18 included a study of various conversions of 4,5-dichloro-2-methylpyridazin-3-one 17 including nucleophilic substitutions, Suzuki reactions and electrophilic substitution (nitration), combined with reductive dehalogenation, and usefully summarised previous work <06T121>. 

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