Ethers

Question 1

Nu attack on oxacyclopropane under basic conditions

Answer 1

SN2 attack the less substituted carbon, inversion is present (backside attack)

Question 2

Nu attack on oxacyclopropane under acidic conditions

Answer 2

SN2 attack at the more substituted carbon

Question 3

Organometallic attack on oxacyclopropane

Answer 3

SN2-like attack at the less substituted carbon, inversion is present. This is because grignards act like bases, and under basic condition there is attack at the less substituted carbon