Organometallic and oxygen I often read that reactive organometallics must be handled under an inert atmosphere because they react with oxygen in the atmosphere. This applies to grignard reagents, organolithium reagents, and organozinc reagents.

What is the reaction of these organometallics with oxygen? I don't see how oxygen can be electrophilic. Maybe it forms a peroxyacid?
Grignards react with molecular oxygen to form hydroperoxides. According to this paper  here the yield for alkyl hydroperoxides can be as high as 90%, yields from aryl Grignards are lower (10-20%).