Question

What are the major products of these aldol reactions?

Both reactions begin with removal of an alpha hydrogen.

Answer 1

Well, assuming removal of an alpha hydrogen, rather than nucleophilic attack of the carbonyl carbon (as one might have expected with the aldehyde...):

`1)`

After forming the enolate, it searches for an electrophilic site. Not much of a good one to find but another molecule of its kind. Given the high heat this is probably plausible...

It could go either way on the last step; either the ethoxide leaves as ethanol or it stays and the oxide gets protonated... I think the former is more stable.

(If that is not correct, the other possibility is from protonating the carbonyl oxide and leaving the ethoxide group attached.)

`2)` Here, the product is easier to be sure about. `"H":^(-)` isn't going to be a leaving group anytime soon.