Orgo help please

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hope_to_match

Full Member
10+ Year Member
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Can someone explain to me why in acidic conditions you can go all the way to form ketal/acetal but in basic stop at hemi? Thanks
 
In Acid, the protonation of the HO in the hemiketal causes it to leave as H20 and thus allow for another nuc. to attack there due to the carbocation. However, in basic conditions, you can't protonate the OH group so it stops there.