Write structure formulae and names of four possible aldol condensation products form propanal and butanal. In each case. Indicate which aldehyde acts as nucleophile and which as electrophile.

Explanation

(I ) propanal as electrophile as well nucleophile
` CH_3 CH_2 CHO +CH_2 CH_2 CHO to overset(5)CH_3 overset(4)CH_2 overset(OH) overset(3|)CH-underset(CH_3)underset(|)overset(2)CH-overset(1)CHO`
(ii ) propanal as electrophile and butanal as nucleophile
` underset("(electrophile )")(CH_3 CH_2CHO ) +underset("(Nucleophile )")(CH_3 CH_2 CHO ) overset ( d i l OH^(-)) to overset(6)CH_2 overset(5)CH_2 overset(4)CH_2 overset(OH) overset(3|)CH - underset(CHO) underset(1|) overset(2)CH -CH_2 CH_3 `
2-Ethyl-3-hydroxypentanal
(iii ) Butanal as electrophile and propanal as nucleophile
` underset("(Electrophile )")(CH_3CH_2CH_2 CHO ) + underset("(Nucleophile)")(CH_3CH_2 CHO ) overset(d i l OH^(-)) to underset("3-hydroxy -2-methylhexanal ") (overset(6)CH_3 overset(5)CH_2 overset(4)CH_2 overset(OH) overset(|3)CH- underset(CHO) underset(1|)overset(2)CH-CH_3`
(iv ) Butanal as electrophile as well as nucleophile
` CH_3CH_2CHO +CH_3CH_2CH_2 CHO overset(d i l OH^(-)) to overset(6)CH_3 overset(5)CH_2 overset(4)CH_2 overset(OH) overset(|3) CH - underset(CHO) underset(1|)overset(2)CH -CH_2 CH_3`