Primary and secondary amines are readily protected as N-pent-kenoyl derivatives, the resulting N-pent-4-enamides being usually highly crystalline. Deprotection is rapidly and efficiently effected under mild conditions by treatment with 3 equiv of iodine in aqueous THF solution. Although an oxidizing medium, these deprotection conditions do not affect oxidizable functionalities including p-methoxybenzyl ethers and alkyl sulfides,
