reaction – nucleophilic acyl substitution

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Reaction – Nucleophilic acyl substitution Yixun Xing

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Reaction – Nucleophilic acyl substitution. Yixun Xing. Reaction . Reaction Mechanism. Reaction Mechanism. Nucleophilic Substitution— - PowerPoint PPT Presentation

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Reaction Nucleophilic acyl substitution Yixun Xing

Reaction

Reaction Mechanism

Reaction MechanismNucleophilic Substitution A fundamental class of substitution reaction in which an "electron rich" nucleophile selectively bonds with or attacks the positive or partially positive charge of an atom attached to a group or atom called the leaving group; the positive or partially positive atom is referred to as an electrophile.

Nucleophilic acyl substitution

Upon attack of the nucleophile at the carbonyl group, a tetrahedral intermediate is formed with the nucleophile, the leaving group and the oxygen anion attached to the central carbon atom. The alkoxy group can now revert back to the carbonyl group and at the same time expel the leaving group. Homo:MO28 Energy: -10.89670evLumo:MO29 Energy: 5.31218 ev

Homo: MO 46 Energy: -11.52918evLumo:MO47 Energy: 2.89761ev

Energy GapE(LUMO) -E (HOMO) = 2.89761ev-(-10.89670ev) =13.79431evDistance: 4.0

Distance: 3.5 Distance: 3.0

Distance: 2.5 Distance: 2.0

Distance: 1.8

Distance: 1.6

Distance: 1.4

Distance: 1.2 Distance: 1.0

Product

Homo: MO 56 Energy: -11.16780ev

Lumo: MO57 Energy: 2.76860ev16ConclusionEnergy GapE(LUMO) -E (HOMO) = 2.89761ev-(-10.89670ev) =13.79431ev

LUMO & HOMO