The efficient succinylation of the sterically hindered tertiary alcohols 1 was performed by reaction with succinic acid monomethyl and monoallyl ester (4a and 4b), respectively, in CH2Cl2 in the presence of dicyclohexylcarbodiimide and 4-(dimethylamino)pyridine under high pressure to give the methyl and allyl succinates 5a and 5b, respectively, in high yields. The succinates 5a,b were efficiently converted into the hemisuccinate 3a by treatment with lithium propyl mercaptide or by palladium(0)-catalyzed deallylation.