How to Predict the Major Product(s) of a Neighboring Group Participation Reaction - Part 1

Neighboring group participation or NGP is also referred to as anchimeric assistance.


NGP is defined by the IUPAC (international union of pure and applied chemistry) as the interaction of a reaction center with a lone pair of electrons in an atom or the electrons present in a s─ or p─bond contained within the parent molecule but not conjugated with the reaction center. The reaction rate is normally increased when NGP is in operation. The stereochemistry of the reaction may be unexpected as well.

Question:

Predict the major product(s) of the following reaction:



Click/tap to enlarge the image

Solution infographic:




Click/tap to enlarge the image

lp = Lone pair, THF = Tetrahydrofuran

Looks easy❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

Reference:

Wikipedia Contributors. Neighbouring group participation. Wikipedia.‌

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