Substitution Electrophilic Aromatic

Found 6 free book(s)

Reactions of Benzene & Its Derivatives

colapret.cm.utexas.edu

Electrophilic Aromatic Substitution • Electrophilic aromatic substitution: a Electrophilic aromatic substitution: reaction in which a hydrogen atom of an aromatic ring is replaced by an electrophile • In this section: – several common types of electrophiles – how each is generated – the mechanism by which each replaces hydrogen + + H ...

Aromatic, Substitution, Electrophilic aromatic substitution, Electrophilic, Electrophilic aromatic substitution electrophilic aromatic substitution

Chapter 15: Benzene and Aromaticity

as.vanderbilt.edu

Benzene undergoes electrophilic substitution reactions (chapter 16) rather than electrophilic addition +BrBr Br Br Br +HBr Fe catalyst electrophilic addition electrophilic substitution Stability of Benzene: Heats of Hydrogenations + H 2 + 2 H 2 + 3 H 2 + 118 KJ/mol + 230 KJ/mol calc'd value= 336 KJ/mol 6 KJ/mol added stability

Substitution, Electrophilic, Electrophilic substitution

Reactions of Aromatic Compounds - Rutgers University

crab.rutgers.edu

toward electrophilic aromatic substitution, and that the methyl group is an activating group). 2) Nitration of toluene generates a mixture of products. The major products are those with substitution at the ortho and para positions. (This preference for o/p substitution makes the methyl group an ortho/para director).

Aromatic, Substitution, Electrophilic aromatic substitution, Electrophilic

Reactions of Fats and Fatty Acids

butane.chem.uiuc.edu

electron poor and so an electrophilic center. The oxygen if methanol has 2 lone pairs of electrons, making it a nucleophile. Before nucleophilic substitution can take place, the alkoxide oxygen on the ester must be protonated to make it a better leaving group.

Acid, Fatty, Substitution, Electrophilic, Fatty acids

Cambridge International AS & A Level

www.cambridgeinternational.org

4 (a)4-nitromethylbenzene can be prepared via an electrophilic substitution reaction as shown in Fig. 4.1. CH 3 conc. HNO 3 conc. H 2 SO 4 methylbenzene CH 3 H NO 2 intermediate T CH 3 NO 2 4-nitromethylbenzene Fig. 4.1 (i)This reaction also forms an isomer of 4-nitromethylbenzene as a by-product. Draw the structure of this by-product. [1]

Substitution, Electrophilic, Electrophilic substitution

Aromatic Compounds

www.crab.rutgers.edu

Ch16 Aromatic Compounds (landscape).docx Page 4 Unusual Behavior of Benzene Benzene has much more stability than predicted by the simple resonance delocalized structure. For example, we know alkenes can be oxidized to syn diols (KMnO 4) and undergo electrophilic additions with halogens (Br 2). Yet the same reactions do not work with benzene.

Aromatic, Electrophilic