side reactions of deprotonation

Dear Sir,

I did a synthesis of : triethylene glycol monomethyl ether with Allyl Bromide, with the help of Sodium Hydride (NaH) to promote the deprotonation.
The expected end product is "allyl methyl triethylene glycol".
What is the possible side reactions which can lead to low boiling point of the end product?
What is the effect if the reaction is not done under Inert ambience (Nitrogen)?

THank you for your kindness.