Warning: When working with esters and bases, be sure the base matches the ester, otherwise you may end up with unintended trans-esterification results.
Note: Carboxylic acids can be prepared from more reactive derivatives like acid chlorides by hydrolysis, in this case under basic conditions. Note that the base will deprotonate the resulting carboxylic acid following the primary reaction.
Note: Saponification of an ester, driven by base. The exchange of water vs. the ester alcohol should be a reversible equilibrium, but subsequent deprotonation of the resulting carboxylic acid makes this an irreversible reaction.
Warning: Base driven hydrolysis of amides will not work when acid-base reactions can occur first. Even for tertiary amides, hydrolysis is an unlikely result.
Warning: Direct enolate alkylation driven by base will not be very effective as simple Sn2 substitution of the base / nucleophile against the alkyl halide is more likely to result.
Note: Direct enolate alkylation of a double active methylene group is more likely as deprotonation will readily occur.
Note: Gabriel synthesis of primary amines starts with deprotonation of phthalimide to produce a good nucleophile.
Note: The cyanohydrin breaks down under basic conditions to yield an aldose, one carbon shorter than before the Wohl degradation.
Note: E2 - Hydroxide ion is a strong base
Note: Sn2 - Hydroxide ion is a strong nucleophile